Hugh Janus

Tobacco’s women’s riding jeans provide ultimate comfort and abrasion protection for the casually dressed rider. (Jeff Allen /)It was the 2019 HighPipe motorcycle festival at Mountain High Resort in Wrightwood, California. I walked the grounds and took stock of the motorcycle riding gear, insurance, and manufacturers’ products on display at the lodge. Among the various companies represented was LA-based Tobacco Motorwear Company. The casual gear under Tobacco’s tent intrigued me enough to try on some of its offerings—or was that the marketer doing their job? I tried the Jet Black riding jeans and then the Indigo ones and loved the fit of both. They were incredibly snug. At the end of the day, however, I did not buy them. The $300-plus price seemed a bit steep for something that didn’t have D3O impact armor included; I find that defense against impact would have been a plus. But, ah, they were so comfortable. And they did offer heat and abrasion protection with the DuPont Kevlar lining. Flash forward a couple of months and I receive a gift from my husband. Lo and behold…the Indigo Tobacco jeans were unboxed. I immediately tried them on again and knew that we were meant to be together—me and my husband, of course. If you get moto gear as a gift from your significant other you know you got a keeper. How They Look And Protection They Offer Aside from possibly recognizing the brand name as a motorcycle apparel company I bet you would be hard-pressed to figure out if these were casual, everyday street jeans or if they were riding jeans. No bulky armor thickens the knees (although the lack of impact armor and armor pockets is a drawback), but rather a layer of DuPont Kevlar lines the buttocks and front of the legs all the way down to the shins. This neon green liner is one of the only other hints that these jeans are suited for something more than a casual pant. With just enough flex, the jeans fit comfortably both on and off the bike. (Jeff Allen /)How They Fit And Feel I find that size 29 accommodates my thin-ish 6-foot-tall frame well. It sits very comfortably on my hips, hugs nicely at the thighs, and hits perfectly at the ankles. Sizes range from 24–40, which is an extensive offering for various body types. The 2-percent stretch denim allows for just the right flexibility when swinging a leg over the bike and does not bunch up in the crotch or knee areas when in a riding position. With other motorcycle jeans, I have had a problem with bunching behind the knees and chaffing in that location as well, however, the Tobacco jean material is soft and supple enough for ultimate riding comfort. Size 29 is perfect for my 31-inch waist and 32-inch inseam. (Jeff Allen /)What They Cost As mentioned earlier, the sticker shock did have a bit of a zap to it. A retail price of $339 is somewhat high considering there are others in the market that sell for about $100 less. But what you are paying for is supreme comfort. That’s really what it comes down to. The Tobacco jeans are very comfortable while still offering more surface area of the abrasion-resistant liner than its competitors. Now that I have these Tobacco jeans in my moto gear wardrobe (and have the potential to mix it in with my casual jeans accidentally) I am very happy that I ended up with these and will probably throw in a few hints to my husband to get me the black ones as well. Source

Technical Editor Kevin Cameron shares his wealth of motorcycle knowledge, experiences, insights, history, and much more. (Cycle World/)When I had accumulated some ­basic experience as quite a young man, I realized there were clear ­national styles in motorcycle engines, but in this new century, I see such ­diversity receding in favor of a new ­international style. I saw that British designers ­reacted against oil leakage and Times of ­London gasket material by employing a multitude of screws to hold case covers in place. Examples are the attractive, polished timing covers of British twins, but the extreme is exemplified by the cam covers of the Rolls-Royce Merlin aircraft V-12, secured by nearly 30 fasteners each. Also very British was too few crankshaft main bearings—as in giving a parallel-twin or even an ­inline-four just two of them, and “­lettin’ ’er flex” in jump-rope fashion. Also ­essentially British in nature was the assumption that a taper alone, without key or other form of angular ­location, could be trusted with ignition timing. Assemble the taper loose, align crank and magneto as desired, then give “a sharp rap with a small hammer and do up the nut. She might move a wee bit in the first gallop or two, but then she’ll bed in.” Muddling through. German design, by considerable contrast, was a demonstration of the extreme capabilities of that nation’s machinists, often requiring the use of liquid nitrogen in the performance of shrink fits. Where a British crankshaft was assembled with tapers and nuts (all of the classic singles were thus) and was then aligned by soft hammer and dial gauge, a German crank such as that of the Adler two-stroke twin was aligned by finely machined ­radial face splines, drawn together by another favorite: a differential-threaded bolt. German design also ­reflected the extreme physical rationalism of Bismarck’s higher technical universities—that design must begin always from first principles. In my shop is the gap-bed lathe from the German Type-IX U-boat U-873. It is a tour de force of triple security on major assemblies, a multitude of clutches, and rigidity that comes only from aged cast iron. Sign up here to receive our newsletters. Get the latest in motorcycle reviews, tests, and industry news, subscribe here for our YouTube channel. The evolution of American motorcycle design practice stopped in 1913 when Henry Ford’s Model T took the transportation market. Only two years before, high-tech Indians with dog-ring gearboxes had swept the Isle of Man TT 1-2-3. From such creative fluidity American design solidified into slow-turning, large-displacement iron engines in heavily built bikes that could survive in a land of dirt roads. That style was enshrined as right and proper—the American way. Italian motorcycle engine design has been a conflict, with sensuous organic design and the shrink-wrapping of major castings suggesting the mysteries within, versus a contrary impulse to style every crankcase as a massive rib-reinforced ­aluminum egg. I loved the cam-drive wheel case of the Guzzi V-8, and the dense finning of Mondial’s Rebello, then wondered why so much aluminum was poured to make each Ducati bevel-drive engine. Spain, a nation new to manufacturing, struggled to produce its ­early Montesas, OSSAs, and ­Bultacos. Not everything was always as it should have been. From a Bultaco ­service bulletin came advice on how to ­combat oil weeping through porous castings: Remove and ­completely dismantle the engine. Then with a ball-peen hammer, the reader was to compress and seal the entire inner surface of the cases by tapping. Improvisation rules. Yet it was ­Bultaco, combining dead-simple two-stroke engines with extreme lightness, who triggered the mass market for ­off-road riding. Motorcycle Engine Architecture (Jim Hatch/)Now much of that national ­design individuality is shifting—toward what I am calling an “international engine style.” An early indicator was the ­engines made for John Bloor’s new Triumph motorcycles. Many called them “English Kawasakis” ­because they appeared in black epoxy finish with shapes closer to modern Japanese practice than to anything from Triumph’s Edward Turner past. In ­recent years, the more new engines I’ve seen, the more they come to ­resemble each other rather than continue the distinct national styles of the past. It was particularly striking to look at the details of Indian’s new PowerPlus big twin, which could have been those of any number of other engines I’ve seen recently. Why should this be so? Around the year 2000 came a casting revolution. Older methods, ­producing fewer sound parts that ­consequently had to be made heavier for ­adequate strength, were replaced by bottom-­fill, low-turbulence methods that produce castings so much ­freer of defects and voids that they have near-forged properties. On a ­before-and-after basis, complete ­motorcycles shed over 30 pounds of excess weight and all welding was automated. There has also been convergence in assembly methods. Out with the old—assembly workers with screw guns—and in with ­completely hands-off simultaneous fastener installation and final torquing. Cases are sealed by robotic pens that write a continuous line of sealant immediately before crankcase closure. To conserve material and ­control weight, major castings fit intimately over the parts they enclose ­rather than being styled into Philippe Starck eggs. Coolant passages are held tight to keep liquid velocity and heat transfer high. Just as Moto2 teams have ­discarded chassis that, while fast, are difficult and time-consuming to set up in favor of those that handle competitively over a broad setup range, so manufacturers have discovered which automatic production systems are most productive, cheapest to operate, and throw the least scrap. This pushes each factory to resemble all other factories. Variety in engine architecture ­remains (as you can see in “Old Souls,” page 58), but beneath it is a sameness. Design for production requires that whatever design choices are made, they must not be allowed to complicate or add costs to manufacturing. In the 1970s, former ­Cycle magazine editor Cook Neilson watched an early CNC machine take half an hour to machine each Ducati twin con-rod, and we learned that the proper adjustment of each bevel-­gear cam drive required seven hours’ work by an experienced technician. Market competition made human handwork too expensive to remain a part of production. Quality today far exceeds ­anything from the honored past, but to combine it with never-ending advanced features and still hit the price point, production methodology and ­economics must rule. Source

Riding the 2020 Husqvarna FE 350s. (Jeff Allen/)The Husqvarna FE 350s model is possibly one of the best dual sport bikes on the market. Significant updates have been made to the Austrian manufacturer’s 350cc four-stroke street-legal dirt bike for 2020. It features Husqvarna’s newest-generation frame, which is stiffer for overall improved handling and straight-line stability. It is the same as the FC 350 motocross and FX cross-country models, as is the engine architecture and bodywork. A WP Xplor 48mm fork and WP Xplor shock handle the suspension duties, while Continental TKC 80 tires are mounted on the wheels for a long life and a very quiet ride. To improve highway comfort, the rim locks are left off, but are included in the tool kit with the purchase of the bike. 2020 Husqvarna FE 350s Engine As of the new decade, Husqvarna manufacturers four 350cc four-stroke models. The street-legal version is the FE 350s. (Jeff Allen/)The FE 350s engine is a true Husqvarna 350cc four-stroke, but it is set up to meet all EPA regulations and be street-legal. This may not sound like a big deal, but making a competition engine run well with those requirements is not an easy task. Emissions are something that we have been dealing with, but compounding the regulations are the noise restrictions. Mufflers are easily quiet enough to pass sound tests, but now the engine has to be quieter. One of the things Husqvarna does to accomplish that is putting a reed valve in the airbox to reduce intake noise. Other EPA factors include a smaller-diameter header pipe with an O2 sensor, a catalytic converter stuffed into the mid-pipe, and an end cap with outlet holes that are about the same size as the salt shaker on your kitchen table has. On the dyno, the restrictions are painfully obvious, as the FE 350s makes 16.3 less peak horsepower than the FX 350 cross-country model. In order for it to be street-legal, the FE 350s is set up to meet all EPA regulations. Because of this, it makes 16.3 less peak horsepower than the FX 350 cross-country competition model. (Jeff Allen/)In comparison to the FC 350 motocrosser or FX 350, the FE 350s is down on power, but that really does not take any of the fun away. The thing that is easily taken for granted is how smooth it runs. It starts perfect, idles smoothly, and has zero hesitation when you crack the throttle. The engine never flames out and has little to no engine decel pop. In the tightest of trails, the gearing is decent. This combined with the smooth power means there is minimal clutch use necessary and in turn, the engine runs cooler; I never experienced any overheating. The only time you may want a little extra power is if you decide to climb some hills that are actually meant for a competition bike. Although the FE 350s’ engine is down on power compared to the FC 350 motocrosser or FX 350 model, it has excellent running characteristics. It starts perfect, idles smoothly, and has zero hesitation when you crack the throttle. (Jeff Allen/)The six-speed gearbox has a super-low first, normal second, and is taller from third through sixth gears. The 14:48 gearing works well and gives you plenty of top speed, making it easy to ride, even on the 70 mph interstate highways. The clutch action is smooth and predictable. I had no issues with the Magura hydraulic system on this bike. 2020 Husqvarna FE 350s Suspension & Chassis/Handling For 2020, Husqvarna’s 350cc dual sport features a stiffer frame and new bodywork. The WP Xplor 48mm fork and WP Xplor shock have updated settings, while the engine features a lighter cylinder head, new camshafts, and a different head gasket that increases the compression ratio from 12.3:1 to 13.5:1. (Jeff Allen/)The FE 350s’ suspension components are the most current model of the WP Xplor 48mm fork and WP Xplor shock with linkage. The FE 350s chassis received all the major updates the motocross and cross-country bikes were granted in 2019 as well. The new frame features increased stiffness for improved rider feedback, better energy absorption, and increased stability. The radiators have been lowered 12mm in an effort to lower the center of gravity. The carbon composite subframe is 250 grams lighter and 50mm longer with more rigidity for improved rider comfort. The bodywork has also been updated and the ergonomics are specifically tailored to deliver greater comfort and control. The contact points have been slimmed down and because of the new wiring harness, the seat height is claimed to have been reduced by 10mm. The Xplor fork is an open cartridge, coil-spring design and is configured specifically for enduro. Adjustments are made via the clickers on the top of each fork leg. It has an added benefit of external preload adjuster that can be moved without tools. The Xplor shock has updated base settings to match the new frame and front end. Although the suspension is cushy and works well in low-speed areas, it is simply too soft in stock form for anyone above a novice off-road rider. (Jeff Allen/)The FE 350s feels very light and nimble. Its smooth power and soft, cushy suspension make it fun in rocks and in tight, low-speed sections. While it works very well at low speeds and on the road, there is a point where you can find yourself using up all of the travel and still wanting to go faster. The fork is easy to adjust and offers external compression, rebound, and preload adjustments. Unfortunately, the front suspension is simply too soft in stock form for anyone above a novice off-road rider. You can somewhat compensate for the suspension with riding style. Decreasing the preload on the shock, thereby lowering the rear end, can also assist to move more weight to the back of the bike. On flowing single-track, it is still manageable, but when it comes to heavy braking or downhill canyons, the front end can become hard to manage. 2020 Husqvarna FE 350s Overall Impression The FE 350s is a light and maneuverable dual sport bike. (Jeff Allen/)The 2020 Husqvarna FE 350s is a very fun bike to ride. It’s a dirt bike first and street-legal second. Obviously, there are few things that you may want to change before you take it to your favorite two-track road. First, the tires. While they are super quiet on the pavement, they fall short on their off-road capabilities. Fortunately, there are quite a few options for DOT-approved knobby tires. After you pick up a set, be sure to add the rim locks while you are mounting them. Also, if you plan on doing longer highway rides, consider two rim locks per wheel to reduce the possibility of the wheels being out of balance. With the new knobby tires, you may want to consider a more compact taillight license plate holder, as over time it will catch in the rear wheel. If you are thinking about purchasing an FE 350s and want to ride it more off road than on road, I would suggest getting some suspension upgrades and leaving the engine alone. It will be very easy to improve on the stock suspension. If you think you are going to improve on the engine power by changing the exhaust or removing parts here or there, you need to be careful. Any change to the engine or its external parts will require different EFI and ignition mapping. While it is down on peak horsepower, the engine runs excellently as is, and with modification, it could easily go backward. Overall, what the FE 350s lacks in high performance, it makes up for in high enjoyment. Ride days of 150 miles from your house to the tightest of trails, fire roads, and back are no problem for the FE 350s. Gearbox The FE 350s has a high fun factor. It’s a dirt bike first and street-legal second. (Jeff Allen/)Helmet: Shoei VFX-EVO Goggle: 100% Racecraft Plus (+) Jacket: Thor MX Terrain Jersey: Thor MX Pulse Air Gloves: Thor MX Rebound Pant: Thor MX Pulse Air Boots: Sidi Crossfire 3 SRS 2020 Husqvarna FE 350s Tech Spec PRICE $ 11,099 ENGINE 349.7cc, liquid-cooled, single-cylinder four-stroke TRANSMISSION/FINAL DRIVE 6-speed/chain MEASURED HORSEPOWER 32.8 hp @ 10,100 rpm MEASURED TORQUE 20.5 lb.-ft. @ 7,600 rpm FRAME Steel central double cradle FRONT SUSPENSION WP Xplor 48mm inverted fork adjustable for spring preload, compression damping, and rebound damping; 11.8-in. travel REAR SUSPENSION WP Xact shock adjustable for spring preload, high-/low-speed compression damping, and rebound damping; 11.8-in. travel FRONT BRAKE Magura 2-piston caliper, 260mm disc REAR BRAKE Magura 1-piston caliper, 220mm disc WHEELBASE 58.5 in. MEASURED SEAT HEIGHT 36.7 in. FUEL CAPACITY 2.2 gal. MEASURED WEIGHT 258 lb. wet AVAILABLE Now CONTACT husqvarna-motorcycles.com Source

This is Walter Zeller at the German GP in 1957 at Hockenheim, where he finished third behind the two Gilera 500/4s of Libero Liberati and Bob McIntyre. Although the photographer identifies him in this year as a “<em>privat-fahrer,</em>” the year before on a factory BMW Zeller was second in the 500 championship behind John Surtees. That was the first 500 title for MV Agusta, made somewhat easier by the reduced participation of Gilera that year. This was the last year for full streamlining as rules with effect from 1958 would require the present form of fairing that completely exposes the front wheel. Today’s fairings impose aero drag similar to that produced as an airliner extends its undercarriage for landing. Evident are the long slow-taper megaphones preferred by the German builders (and soon adopted by Honda) for the wider powerbands they fostered. See also the finned under-engine oil sump, and possibly the use of fuel injection. This bike’s intakes are very different from those seen a year later on carbureted engines ridden by the late Geoff Duke. (Volker Rauch/)Volker Rauch photographed Grand Prix racing. His pictures showed the sport and its practitioners as it, and they, never before had been seen. Working mostly in black and white, using his beloved 35mm Leicas, Rauch made photographs that smack the viewer in the eye with their rightness of composition, exposure, and sharpness, with their sheer artfulness. For a time, Rauch was like the fictional Roy Hobbs in Bernard Malamud’s classic novel of baseball and life, The Natural. He simply was the best there ever was. Respected and rewarded, he lived racing’s high life, wearing the finest clothes, driving the fastest cars, chasing the most beautiful and expensive women. He revolutionized racing photography and set professional standards that still are being recognized and reached for. And then, two years ago, he killed himself. He left a widow, a daughter, a cadre of baffled and brokenhearted friends, and an estimated 100,000 photographic images of roadracing’s giants, made during racing’s golden age on the great and classic racetracks in the world.” —Jon F. Thompson, Cycle World, May 1995 Here is Geoff Duke himself in conversation with 1939 Senior Isle of Man TT winner Georg Meier. The venue is the 1958 Rhein Cup event in Germany. This engine is clearly carbureted and the long leading-link fork of that time is fitted. Note the chin pad affixed to the fuel tank: Tracks were seldom smooth and no one likes to take it on the chin. (Volker Rauch/) Detail of 1950s BMW front end with long leading-link fork and the hefty steering damper required to calm its motions when the rider has only the narrow clip-on bars pictured. Note also the substantial rear anchorage of that damper. (Volker Rauch/) RELATED: More classic Volker Rauch photographs in Part 1 MV Agusta factory riders confer. Is that Count Agusta himself with hands on hips? Nobody looks pleased. On the bike is Carlo Bandirola (many top placings but no GP wins), while the spare-looking fellow beside him is Umberto Masetti (500cc world champion in 1950 and ’52). This is the Nürburgring, June 1955, and Bandirola and Masetti would finish third and fourth respectively, behind Geoff Duke’s Gilera and Walter Zeller’s BMW. Why are these powerful four-cylinder bikes behind Zeller’s significantly less powerful twin? Because MV had not yet been exposed to the heat of John Surtees’ ambition, and his determination to “anglicize” the not-so-hot chassis of the MV. (Volker Rauch/) April 24, 1955, Dieburger Dreiecksrennen: This is the Horex 350 DOHC twin, which seldom appeared in races outside Germany. It is a feast for the eyes with its very extensive finning, exposed hairpin valve springs, external oil pump with a multitude of braided-steel lines (borrowed from aircraft practice), and its Indian-like ignition distributor. The carburetors are all but invisible, pushed rearward as they are by intake extensions. You can see several small chassis tubes heading for their points of attachment to the cylinder head. This feature and the shape of the Horex production bike’s cylinder head became prominent features of Honda’s Hawk and Super Hawk 250 and 305 twins of the early 1960s, later revived for the CBX 1,047cc six-cylinder. At bottom right can be seen the aft loop of this bike’s leading-link suspension, so trendy in this period. The engine was said to give 36 hp at 10,000 rpm. (Volker Rauch/) A rider in leathers and flat cap enjoys a smoke as he warms up this NSU Sportmax on its stand, hidden in a masterpiece of the panel-beater’s art. Bikes with such metal fairings were extremely noisy as their lack of damping set them drumming, acting as loudspeakers. The large opening cools the engine and the blisters are for handlebar clearance inside the fairing. This same casual “I do this really cool stuff all the time” look can be seen in race paddocks to this day. The fairing has probably been crashed and then only roughly unwrinkled. (Volker Rauch/) Here are the NSU record team and their six streamliners, headed for the US in 1956. They are shoehorned into what may be a KLM Constellation, powered by four huge supercharged piston radial powerplants. The NSUs set a total of 64 records with a variety of engines. With a 500cc engine in the Delphin III, rider Wilhelm Herz set 12 records (four each in 500, 750, and 1,000cc) over 200 mph, including 1 mile at 211 mph. In the iconoclastic feet-first Baumm II streamliner, H.P. Müller set 36 records ranging from 121.7 mph with 50cc engine, to 150 mph with 250cc engine over 1 mile. (Volker Rauch/) NSU techs use a Vernier depth gage and degree wheel to set piston compression height on one of the record engines. More compression can be used on the salt because of the reduced atmospheric density at Bonneville’s 4,237-foot altitude. Note the very large gearbox sprocket, made possible by the high rear wheel speed of a streamliner. (Volker Rauch/) Sign up here to receive our newsletters. Get the latest in motorcycle reviews, tests, and industry news, subscribe here for our YouTube channel. On the right is NSU’s Delphin III streamliner used with the 350 and 500cc engines, and on the left the Baumm II feet-first bike powered by engines from 50 to 250cc. (Volker Rauch/) NSU record-setter Wilhelm Herz (left) looks considerably less at ease than the unnamed Utah sheriff with ammo belt and sidearm as they enjoy drinks after hours. (Volker Rauch/) How’s the salt? Wilhelm Herz touches the white stuff at 122 degrees Fahrenheit. The hat protects his head from burning and peeling but his forearms will become “welder’s pink” if he doesn’t seek cover soon. The mountains look just as lunar today. (Volker Rauch/) How smooth do you want it? What looks to be a length of rail is about to groom the course at Bonneville. (Volker Rauch/) This is the well-attended Hockenheim German GP of 1967. The crowd density indicates that motorcycle sport at that time was mainstream indeed. Today we have YouTube so we don’t need to go anywhere. (Volker Rauch/)RELATED: More classic Volker Rauch photographs in Part 2 Source

Chassis flex can reduce sharp peak forces transmitted to a rider’s body, increasing performance, comfort, and stamina. (Brown Dog Wilson/)We all know that where people work on their feet, everyone is more comfortable and productive if there is cork or rubber flooring. I have spongy rubber floor mats at my porting bench. What do they do? They protect our joints from sharp impacts that, totaled over days and weeks, add up to soreness. Motocrossers speak of chassis “harshness” as setting the upper limit on what they can survive through a full moto. If chassis flex clips the sharp peaks off the forces that it transmits to the human body, that body works better and delivers greater stamina. As I’ve noted before on this site, roller chains couldn’t take over the motorcycle powertrain job until there was a flexible element between them and the engine’s hard combustion thumps. Rollers split and flew off, and joints tightened until some form of spring drive was added for their protection. Come to think of it, I strongly suspect the present long lives of drive chains are not entirely the result of O-ring construction, which seals in and retains lubricant in every chain joint. Also important is the rubber cush drive in the rear wheel which, like chassis flex for MXers, clips the sharp peak forces that would otherwise have hurtful results—in this case more rapid fatigue and stretch of drive chains. Why do modern motorcycle engines with digital engine control so often have cylinder-head-mounted accelerometers? They are there to detect the sharp peak combustion pressures caused by detonation—an abnormal form of combustion. Those peak pressures are known to shock rod and crank bearings into failure while they are doing the more obvious damage of blasting bits of aluminum out of our piston crowns. When detonation is detected, the ECU instantly pulls back ignition timing to stop the knock-knock-knocking before it can damage parts. When Keith Duckworth’s master work, the DFV Formula One engine, went into service in 1967, it would from time to time break a tooth or so off one of its cam drive gears. Calculations had been made to estimate how much torque this drive had to transmit, but the actual forces in the running engine turned out to be 10 times greater. The reason was that both the crankshaft and the cams have their own dynamics, flexing constantly in twist as cylinders fire and valves are heaved up off their seats and set back down again at 1,500 Gs. When one set of parts is trying to go north when another is unwinding to the south, the resulting momentary forces can be tremendous. Since the engine was already in production it would have been very expensive to redesign the whole cam drive, so Duckworth came up with something he could build into one of the gears, containing a circle of tiny torsion bars, each with a little crank at one end. This added just enough flexibility to the drive to clip off the tall force peaks that had been making gear teeth old before their time. Other makers, faced with similar problems, have found solutions in such things as flywheels or dynamic “Napier dampers” (Tootsie Rolls in holes). Or they have tried driving the cams from the flywheel end of the crankshaft, or from its center, hoping for “a quieter life.” There’s a lot more to engine development than ordering in 50 grand’s worth of super-rad parts from the usual suspects and bolting them together. This Honda six crankshaft drives the cams from the center because that location has zero torsional motion. This reduces vibration and impact loading. (John Owens/)When an aspiring World Supersport team’s rider kept reporting something weird in the bike’s rear suspension they hired a crew chief with experience (as opposed to just a youthful willingness to work 24 hours straight and then drive the transporter to Czecho). Removing the spring from the rear suspension unit, he then cycled the assembly through its full travel. Or tried to. There was a glitch, a momentary resistance at one point. That, added to what the rear tire was already being asked to do, was sometimes too much. It was kicking the back end loose without warning. Gotta watch those peak loads. Aircraft structures are “lifed” for a specific number of total flight hours. Such calculations are based upon years of experience with gust load intensity encountered at various altitudes, based upon the aircraft’s mission requirements. What puts an end to the life of an aerostructure? Fatigue or stress corrosion cracking, as a result of X spectrum of stresses. At present a new technique has been brought to bear on this problem: gust relief. What if, as a gust suddenly begins to accelerate a wing upward, the aileron on that wing were quickly deflected to reduce the severity of the gust load? It works. I also recall reading that the long-serving B-52 bomber’s airframe was lifed for operation mainly at high altitude where low atmospheric density just can’t muster as many bumps and thumps. When those aircraft were brought down to lower altitudes for use in the Southeast Asia war their airframes fatigued considerably faster owing to rougher air. Rougher air at low altitudes fatigued the B-52’s airframe faster than at high altitudes where the low atmospheric density had less impact. (U.S. Air Force photo by Senior Airman Juan Torres/)This begins to sound a lot like what Ducati has done with its Evo2 anti-wheelie system. Instead of waiting for the wheel to rise a certain distance before intervening (by reducing engine torque a bit), Ducati’s system looks for a rapid initial upward acceleration rather than a specific upward displacement. And now helmets. A famous movie star regarded a motorcycle helmet as a serious infringement of his personal freedom, so when he had the misfortune to tip over, in the resulting tumble he hit his head on something hard with nothing between to clip the sharp peak off of the impact force. That peak load made his hospital stay a lengthy one. Same with auto-inflating “air bag” riding suits. That collarbone may not break this time if, as your shoulder approaches ground zero, a suddenly inflated air bag clips the sharp spike off of the impact. I mustn’t leave out the ultimate impact-reducing system, essential to every vehicle, operator, and passenger: the brakes. Source

Oil viscosity is affected by temperature—at both ends of the thermometer. (Cycle World Archives/)I stepped off a train at wintry Westport station near New York City, pulled my suitcase off the rack, and went looking for my ride: an ancient black Buick straight-eight. I found it with other long-term cars in a snowbank. Eventually I made a way to the driver’s door and sat at the wheel. Key above the sunshade—there it was. Now the terrible contest—battery and starter versus the Pleistocene. The starter turned, but so slowly. I’ll have to walk the 5 miles. I could hear the grr of tooth engagements of the starter pinion against the ring gear. Grinding. Surely it’s too cold for sparks to ignite gasoline. Grinding. I thought about the congealed oil on cylinder walls, in bearings, resisting all motion. But the battery kept turning the starter until there was a single jump: A cylinder had fired. Again. Shall I drive rather than walk? Oil viscosity is both bane and benefit. Oil, thickened by low temperature, resists all motion. It has become glue. But oil’s viscosity in the fast-moving loaded zone of a crankshaft bearing is what keeps it from being squeezed out by the load. That resistance keeps enough oil moving through the bearing to support the load. Had that Buick’s oil sump contained a modern multi-grade oil I’d have been spared that drama—the engine would have spun over and fired at once. The point I’m making is that oil viscosity rises at low temperature and falls at high temperature. It’s a fight between the affinity of the long-chain oil molecules for each other and the vibrating energy of temperature. In the 1930s, Benelli in Italy borrowed from aviation practice by mounting an oil cooler on a bike. And it took a patent on the idea. When Honda went GP roadracing, starting in 1959 at the Isle of Man, it quickly encountered severe oil viscosity loss at high temperature, and suffered some outright engine seizures. We’re talking four-stroke engines here; so what was happening was that in summer operation, oil in air-cooled race engines was losing so much of its viscosity that piston lubrication was occasionally breaking down completely. In quick succession Honda tried the “English answer,” carrying the oil in a separate, remote tank, and it tried the “Italian answer,” which was to provide a long finned aluminum sump under the engine. Since neither was adequate, in 1965 it integrated small oil coolers into ducts in the bikes’ fairings, such that oil was actively, intentionally cooled rather than cooled by accident. That brought the situation under control, keeping oil from getting hotter and hotter until it “turned to water” and bad things happened. I saw Honda’s oil coolers at the Canadian GP in 1967, dangling from their hoses after fairings had been removed. Success. Oil acts as both lubricant and as heat-exchange fluid. Oil can go places where air and water cannot. It cools internal parts such as pistons, valve springs, and bearings, tending to level all temperatures. Certain styling departments reflexively dislike oil coolers—rather like the vain young biologist I once encountered, who upon arriving at work invariably put his wallet in a desk drawer, explaining that “It spoils the line.” Okay, maybe even better than an oil cooler is a water-to-oil heat exchanger (the spin-on oil filter often mounts on such an exchanger) because the rapid warm-up of engine coolant sees to it that the oil warms up just as fast. Why do we care how quickly the oil warms after starting? We care because any cycle shop service manager can name for you the older models whose sluggish cold-start oil circulation led to problems like premature cam or bearing wear. In an ideal world, every engine would have an electric pre-lube pump that pressurized the oil system just before starting. Although liquid-cooling has solved many durability and running problems, cooling by internal oil circulation remains essential. In the case of air-cooled engines, which tend to run too hot in hot weather and too cool in cool weather, oil cooling has a long history of giving aid where needed. The large air-cooled radial piston engines that powered so many aircraft in WWII (all US bombers, plus the P-47, F4F, F4U, F6F, plus all ground-attack types) relied upon oil cooling for about 30 percent of their waste heat removal. Therefore it is just continuing that great tradition when present-day builders of iconic air-cooled designs need to supplement what cooling fins can do by adding oil coolers plus strategic circulation through cylinder-head passages. This includes several Harley-Davidson models, the large BMW twins, and at least one of Honda’s large “cooling-fin revival” four-cylinder jobs, in which the official line is that the supplementary cooling is just for the spark plugs (nudge, wink). Fins for cooling, on the cylinders and on the oil cooler on this Harley-Davidson Street Glide, keeps the oil in the proper temperature range so that the engine oil’s viscosity can do its job. (Kevin Wing /)Let’s not kid ourselves. When oil cooling is necessary, the job is keeping oil in the temperature range in which its viscosity can carry engine loads. Putting the cooler in a desk drawer “because it spoils the line” may cut it at art school, but it’s poor physics. Source

Can you fold your way to two-wheeled freedom? Give it a try with our Energica Ego papercraft template. (Chris Philpot /)Young or old, there’s never been a better time for crafts than now. In that spirit, we commissioned this paper template so you can fold your way to two-wheeled freedom right at the kitchen table. The Energica Ego electric motorcycle’s crisp lines are perfect for translation from two dimensions into three, so fire up your printer and get started. We have added vibrant colors, but may we also suggest you print in black and white so you can pick your own graphic scheme. We’d love to see what you built. Tag @CycleWorld along with the hashtag #papermotorcyclechallenge. Print this template and get to work. Should we make more of these? What motorcycles would you like to bring to life? Ducati Panigale V4? BMW R nineT? KTM 790 Adventure? Yamaha Ténéré 700? Honda Monkey? Suzuki Katana? Let us know in the comments below! Source

Debuted in 1985, the Honda Rebel has been bringing beginner riders to the sport for decades. The model saw significant changes in 2017 and now, for 2020, Honda keeps the updates coming to further entice its intended audience. The added assist and slipper clutch, suspension refinements, modern LED lighting, a new gauge layout, and a thicker, more dense seat are all part of the 2020 package. After receiving a significant face-lift in 2017, the Honda Rebel 500 returns for 2020 to attract female and newer riders to motorcycling. (Jeff Allen /)Honda told us its primary target is women and beginner riders. In fact, the manufacturer shared some numbers showing that a growing portion of Rebel owners are women with 36 percent of owners for the 300 and 28 percent for the 500. It also found that an impressive 61 percent of Rebel 300 purchasers are first-time owners and 45 percent are first-time owners for the 500. This shows that while both females and first-time owners have their sights set more on the 300 model, there is still a significant percentage who end up opting for the 500. I don’t blame the latter percentile’s higher interest in the 500 as it is not as intimidating as the displacement may imply. The Rebel is powered by a 471cc parallel-twin engine. A helpful beginner addition this year is the assist and slipper clutch which makes clutch lever pull lighter. (Jeff Allen /)A key update that will be helpful to a beginner is the new addition of the assist and slipper clutch. This is said to reduce lever effort by 30 percent and, in practice, the clutch pull was very light eliminating any intimidation factor that a tougher lever actuation may present. The Rebel’s 471cc powerplant remains unchanged for 2020, and I found the power is smooth and manageable, with plenty of low-end torque for getting off the line and enough horsepower to pull the taller gears for cruising and moving at highways speeds. We ran the 500 on the Cycle World in-house dyno and concluded that the parallel twin makes 40.8 hp at 7,900 rpm and 29.9 pound-feet of torque at 6,300 rpm at the rear wheel. Another change is that suspension has been stiffened. Under large, harsh bumps the rear end did buck up, but over potholes or rough roads you will encounter more often, both front and rear were stable. (Jeff Allen /)Honda says spring rates have been stiffened to improve overall comfort and handling. As a result of the increased stiffness, I found that the Rebel 500’s front suspension under hard braking was firm, keeping the chassis balanced and limiting front-end dive under hard braking. Rebound damping was quick initially but slowed on its return to static ride height. Generally, the 41mm fork and twin shocks felt stable over potholes and rough roads with 4.8 inches and 3.8 inches of travel, respectively. However, under larger, harsher bumps the rear did bottom out causing the bike to feel unstable at the rear when I was bucked up out of the seat. Braking with the Nissin hydraulic disc brakes is strong and communicative. (Jeff Allen /)Nissin hydraulic disc brakes are employed by Honda at the front and rear. They do not have a hard initial bite (as should be expected from a beginner-friendly motorcycle) but a strong and communicative feel pulls the bike to a smooth stop as you increase lever effort. This is a positive aspect for beginner riders who need a more controlled, steady stop upon a fast, tight squeeze that can come from less experienced fingers. Both the 300 and 500 are also available in ABS options at a $300 addition to the base MSRP—a solid choice for new and experienced riders. The Rebel’s low-slung weight keeps the bike planted in the turns and twisties. ( Jeff Allen/)The Rebel 500 carries its weight down low which makes not only picking it up off the stand easy but taking the twisties with confidence as well. Hitting the crest of the turns the bike was planted thanks to its low center of gravity and the power pulled it out of the turns with a tame sweep that was confidence inspiring. Without the saddlebag accessory the Rebel 500 tipped our scales at 418 pounds and weighed 422 pounds with the saddlebag attached. The four-lamp LEDs really add to the overall aesthetic and are one of the new additions for 2020. (Jeff Allen /)The new LED lighting throughout is a notable change for the 2020 model year. Four LED lamps are tucked into the circular casing, and LED turn signals and taillight (even the license plate light) are clean and modern. The previous models’ taillight section used to protrude awkwardly, but this has now been tidied up nicely. The new semi-circular gauge is easy to read at a quick glance. (Jeff Allen /)The larger semi-circular LCD gauge is also new. It displays information like time, speed, gear position, and fuel level readout, but is missing a tachometer—an odd omission. Additionally, you can also scroll through the odometer, two tripmeters, average trip mpg, and current mpg. A toggle switch on the hand controls rather than a button on the gauge would be handy, but the Rebel is a more basic ride. Regardless of this, all of the information displayed is easy to read at a quick glance. A comfortable reach to the bars, though the footpeg position is slightly cramped for a 6-footer’s legs. (Jeff Allen /)In terms of the ergonomics I found the riding position to be comfortable for my 6-foot-tall frame. The reach to the bars was natural and relaxed, however, the peg position was slightly compact for my long legs, because it put my knees a little too far above my hips. The accessory seat looks custom with its stitched pattern. It is also updated with the same foam as seen on the 2020 stock seat. (Jeff Allen /)The seat has seen some changes including the thickness and density. Our Rebel test unit was equipped with a seat from Honda’s accessory line, so while we didn’t get a chance to try the stock seat, the foam in the accessory one is also updated to the new 2020 spec. Whether an hour-long or two-hour-long stretch, saddle soreness barely even made itself known with this upgrade. We measured the seat height at a low 27.6 inches (Honda claims 27.2 inches for the stock seat) and its thinness between the legs makes for a very easy stretch to the ground. From the tidier tailsection to the LED lighting and everything in between like the braided hoses, the Rebel’s fit and finish makes it look more expensive than the $6,199 base price. (Jeff Allen /)Honda has paid great attention to the rest of the fit and finish of this motorcycle. It is especially orderly in terms of wiring. The wrapped cables on the handlebars and braided hose covers near the engine show that Honda paid attention to even the minuscule and less exciting details in addition to the updates I mentioned before. And all of these finer points of the finish make this machine look more expensive than it is. The Honda Rebel 500 has an MSRP of $6,199. ABS increases the price to $6,499. (Jeff Allen /)Props to Honda for keeping the pricing unchanged for 2020, despite the upgrades. The base Rebel 300 rings in at $4,499 and the base 500 is $6,199. Both appropriate pricing for entry-level machines. Accessories are available so you can tailor your ride however you like. All of these accessories total out to $410.70. (Jeff Allen /)Our Rebel 500 test unit wasn't quite stock, fitted with elements from Honda’s accessory line. Equipped with the headlight cowl, fork boots, 12-volt accessory socket, custom-looking seat, left 14-liter saddlebag, and saddle bracket, $410.70 was added to the price tag. Overall, Honda’s Rebel 500 carries the torch for the beginner cruiser category and with smooth and torquey power, comfortable ergos, useful updates, commendable attention to detail, and affordable pricing these machines will continue to be enjoyable regardless of gender or skill level. Additional updates on a proven platform continue to make the Rebel 500 an enjoyable ride regardless of gender or skill level. (Jeff Allen /) MSRP: $6,199 (non-ABS)/$6,499 (ABS) Engine: 471cc liquid-cooled parallel twin Bore X Stroke: 67.0 x 66.8mm Transmission/Final Drive: 6-speed/chain Cycle World Measured Horsepower: 40.8 hp @ 7,900 rpm Cycle World Measure Torque: 29.9 lb.-ft. @ 6,300 rpm Fuel System: PGM-FI Clutch: Wet multiplate Engine Management/Ignition: Full transistorized ignition Frame: Diamond-type steel tube Front Suspension: 41mm fork; 4.8-in. travel Rear Suspension: Dual shocks; 3.8-in. travel Front Brake: Nissin hydraulic disc Rear Brake: Nissin hydraulic disc Wheels, Front/Rear: Cast aluminum Tires, Front/Rear: 130/90-16 / 150/80-16 Rake/Trail: 28°/4.3 in. Wheelbase: 58.7 in. Ground Clearance: 5.3 in. Seat Height: 27.2 in. (claimed)/27.6 in. (measured) Fuel Capacity: 3.0 gal. Claimed/Cycle World Measured Wet Weight: 408 lb./418 lb. (w/o saddlebag), 422 lb. (w/ saddlebag) Availability: Now Contact: powersports.honda.com Source

Harley-Davidson, in conjunction with Bonhams, will be auctioning off this custom LiveWire to raise funds for the United Way. (Harley-Davidson /)Harley-Davidson’s trying to do its part. The Motor Company and Bonhams will host an exclusive auction of a one-of-a-kind custom motorcycle and donate the proceeds to United Way Worldwide’s COVID-19 Community Response and Recovery Fund. It’s not unusual for The Motor Company to step up in times of crisis; it has contributed to both US and international relief efforts consistently over the years, from support for 9/11 first responders to donations of bikes in the Haitian earthquake restructuring. The current health crisis is an unprecedented and ongoing one, and H-D is chipping in to raise funds with a customized LiveWire made just for this moment. “We’re all affected by the current situation,” said Jon Bekefy, general manager of brand marketing at Harley-Davidson Motor Company. “As a longtime partner of the United Way, and inspired by their continued resilience in this crisis, Harley-Davidson is honored to have a part to play in the relief effort and to inspire our community about the open road ahead.” Part of the custom treatment on the auction bike include carbon fiber finishes and accessories like this Speed Screen. (Harley-Davidson /)Up for bidding will be an ultra-exclusive version of Harley-Davidson’s electric machine, adorned with a one-off paint scheme and unique graphics package created by the Harley-Davidson styling and design team just for the occasion. This bike, which is a modified “First Strike” edition of the LiveWire (those specially numbered versions celebrating the first 500 units produced) also wears a full array of carbon fiber Genuine Parts and Accessories including carbon fiber Speed Screen Blade, Tail Section Cowl, and Tank Trim. To mark the historical significance, the bike on auction is number #500 of the 500 “First Strike” edition LiveWires and will be signed by members of the Davidson family. “The Harley-Davidson design team created the custom paint and graphics on this motorcycle to accentuate the natural forms of the LiveWire,” Bekefy said. “It’s a very unique and stunning motorcycle that is truly one of a kind.” The winner will also get special delivery of the motorcycle as well as a hosted, behind-the-scenes private tour of the Harley-Davidson Museum. (Andrew Cherney /)On top of that custom LiveWire, the winning bidder and one guest will also be treated to an exclusive delivery experience and a “behind-the-scenes” tour of the Harley-Davidson Museum. That includes all travel and accommodations to Milwaukee as well as a private, one-of-kind walk-through of the museum. The auction will be held by Bonhams digitally to honor the CDC’s social distancing guidelines, and will open for bids online at this site starting May 12 at 10:00 a.m. EST, closing May 26 at 4:00 p.m. All proceeds will be donated to United Way Worldwide’s COVID-19 Community Response and Recovery Fund. Bidders can find more info about the auction and prize package at bonhams.com/LiveWire, which is available for participants from the United States. Sign up here to receive our newsletters. Get the latest in motorcycle reviews, tests, and industry news, subscribe here for our YouTube channel. Brian Gallagher, president and CEO of United Way Worldwide, is thankful for the help;. “The funds raised by auctioning this customized motorcycle will allow us to better provide needed services for individuals and families recovering from COVID-19 and support our efforts to bring communities back stronger than before.” More info on the LiveWire is at Harley-Davidson.com/LiveWire. Source

Kevin Cameron (Robert Martin/)“Vtt-nn! Bark! Rumble!” Who can resist? Here we all are, waiting for the stoplight to turn green, and we are anticipating departure by blipping our throttles. Why do we do it? Cruiser guys do it. Tenured professors of English literature do it. Because motorcycle engines and their fuel systems have been so civilized for decades, there is no longer any physical reason to blip the throttle. We are not “clearin’ ’er out,” because there’s nothing to clear. All bikes now have near-perfect air-fuel mixture at all times because that’s the job of their digital engine management systems. That became obvious when Cycle World testers used to run for top speeds at their “secret desert road.” Here comes the bike, sounding strong and sharp; 192 mph! Hot stuff. Moments later the test rider rolls back to the group, the bike’s engine burbling happily and stably at idle. Or think of dragstrip riders. As the tree starts down, they smoothly bring the revs up to their chosen launch rpm, hold an instant, and go. No brum-brum, no vtt-nn, vtt-nn. Bring revs to the launch point and go. Yet remember the generations of racing mechanics, warming up bikes with rhythmic bursts of throttle, tach needles swinging back and forth. Hailwood’s Honda 250 six warmed up with a rapid, irregular WOOP-woop-WOOP. Manx Norton 500 singles prepared for action with BRUM-bah, BRUM-bah. It was exciting. It was anticipatory. It was a sonic celebration. But why did they do it? Why not just start the engine, check for oil circulation, and leave the bike to warm up on the stand? There was a real reason for throttle blipping, and in some cases it still exists today in certain racing engines. In a valve train with high-pressure valve springs, it is the nature of the lubrication between cam lobes and tappets that sets the speed of minimum idle. Above some critical speed, the cam lobes are spinning fast enough to generate a full lubricating oil film between themselves and their tappets (this can be measured by such means as electrical resistance between the parts). But below that speed, the slower motion allows more time for lubricant to be squeezed out, leaving only a partial oil film. Anti-wear additives in the oil can help here, protecting bare surfaces from scoring. But in some race engines, idling just destroys the cams. Because oil films need speed to form completely, friction rises at low rpm. Both Professor Heywood at MIT and Paul Jette at Del West (the California makers of titanium valves and pneumatic spring systems) told me that rising friction at low speed puts a lower limit on idle rpm. Jette noted that many racing valve systems will fail promptly if idled. On page 3 of general information regarding the Cosworth Norton JAB engine, dated 5/18/1976, it says, “The engine must not be allowed to idle under 2,000 rpm or excessive cam and tappet wear may be experienced.” That is why racing mechanics for 100 years have warmed up engines by throttle blipping. And that made it cool. Production machines naturally have to be engineered to idle indefinitely without valve train damage (ever shuffle forward for a solid 10 minutes in a long summertime toll queue?). The bikes we buy and ride are given cam lobes and tappets wide enough and valve springs soft enough to guarantee satisfactory lubrication at idle. They have oil pumps that at idle bathe moving parts through a multiplicity of holes through cam lobes, supplied through oil galleries into their hollow interiors. This is just sensible engineering. As superior oil additives and super-hard and smooth anti-friction coatings such as DLC have come into general use, even some of today’s 18,000-rpm MotoGP engines are allowed to idle during warm-up. All that is irrelevant for street riders, who continue to enjoy the sound and fury of a bit of throttle-blipping at stoplights. Its origin forgotten, throttle-blipping has become part of the fun. Source

Going under the sword with the 2020 Suzuki Katana. (Jeff Allen /)In 1980, Cycle World dubbed the four-valve Suzuki GS1100 “the best all-around superbike in history.” It turned the quarter-mile in 11.39 seconds at 118.42 mph. It was arguably the finest-handling Japanese production motorcycle of the time. It was practical; it got 47.4 mpg on the CW test loop, and it was as comfortable as anything without a Windjammer fairing. It was a formidable large-capacity motorcycle with real presence. It may have been exceptional, but the GS1100 was nothing new. Like other iconic superbikes of the era—the Kawasaki Z1 and Honda CB750, for instance—the big GS exemplified the Japanese motorcycle industry’s conservative approach toward design. Wide bars, circular headlight, and bread-loaf seat were the status quo. To the unacquainted in 2020, there aren’t a lot of visual cues that distinguish the era’s sit-up superbikes from the more plebeian UJMs that sprouted in their midst. It’s as if Suzuki product planner Etsuo Yokouchi divined the GS’s inevitable decay—chrome oxidized from years of neglect, vinyl ignominiously patched with duct tape fraying at the edges, steel tank pasted with wet leaves. The 2020 version of the best all-around superbike of 1980 is a forgotten also-ran marooned beside a rotting front porch in the damp corner of rural-town USA. It takes little stretch of the imagination to envision Yokouchi, in search of something future-proof, kicking around the Hamamatsu factory like some bored kid in the backwaters, hankering to change the world. What he came up with was the 1982 GS1000S Katana, a futuristic expression of the Japanese design philosophy of wabi-sabi. Though very much based on the GS1100 platform, Suzuki hoped the Katana’s daring departure from established norms would be the answer to stagnant sales. With its rectangular headlight, triangular fairing, and long two-tone seat, there’s a note of asymmetrical discordance—almost an appearance of being unfinished —that articulates an ephemeral beauty, which is a very wabi-sabi virtue. Intentionally or not, the Katana’s radical thinking comes across as deeply rooted in ancient Japanese philosophy. It’s ironic that it was sketched by the German design firm headed by Hans Muth. The second-year Katana is distinguished from the 1982 model by the blue and navy ribbons down its spine and its 1,074cc displacement. In order to meet racing regulations, the limited-production original had a reduced bore to bring displacement to 998cc. (Jeff Allen /)Yokouchi himself previously designed the X-6 Hustler, the GT750, and the GT250, but his stint as manager of the racing department in 1974 and 1975 crystallized his desire to build a full-on sportbike. The Katana’s clip-on handlebars and rearsets (firsts for a production bike from Japan) and notoriously taut suspension left a physical impression on its rider as uncompromising as its visual one. The Katana was a motorcycle that demanded sacrifice from its rider. The Katana became the first movement in Yokouchi’s symphony of speed. But by the time enthusiasts first laid eyes on it, he’d already begun envisioning his masterpiece. Yokouchi wasn’t content with radical. What he wanted was a revolution. And here we are in 2020 with the legendary Katana badge reborn for a new generation. Like the original, the new Katana is largely based on an existing GS, the GSX-S1000. History repeats itself, with Suzuki entrusting the concept design to an outside firm, this go-around headed by Italian designer Rodolfo Frascoli. “[The challenge was to] make it a redefined modern motorcycle with real novelty,” says Kazutaka Ogawa, Suzuki director of design development, “not a revival or a run-of-the-mill déjà vu [motorcycle].” The 2020 Katana in looks-right Metallic Mystic Silver. (Jeff Allen /)The GSX-S and Katana share the same chassis and both utilize a street-tuned version of the long-stroke (73.4 x 59.0mm) 999cc inline-four from the legendary GSX-R1000 K5. Stainless-steel valves replace the K5’s titanium ones, and revised cam timing and gearing (via two additional teeth on the rear sprocket) conspire to deliver a generous helping of torque throughout the rev range for street-riding bliss. The Katana’s lower gearing means that at 90 mph in top gear, the engine is spinning at 6,000 rpm, and there’s significant buzz transmitted through the bars and pegs. Compared with the semitruck-long original, the modern Katana looks compact and stubby, almost football-shaped. At 475 pounds fully fueled, it’s also around 72 pounds lighter than the original. The seat and tank are relatively narrow considering the four cylinders situated across the frame, but the rider is perched on top—rather than in—the motorcycle. After an hour in the saddle, the seat begins to communicate its, ahem, minimalism. The bars are lower and narrower than on a typical naked bike, so just when you start to feel antsy in the saddle, you also begin to pine for slightly higher, closer bars to accommodate a more upright position. Coupled with the nonexistent wind protection, the only option is to hunker down in search of a clean pocket of air and a different position to give the shoulders a break. Etsuo Yokouchi. (Cycle World Archives/)But if one must hunker, finding a twisty road to do it on is the natural choice. There, you’ll be dropping your head and hanging off anyway, and the Katana will be at home in its corner-terrorizing habitat. Heading into Borrego Springs on S22 (er, make that “the S22,” to use the Californian’s vernacular) is a reminder that once you escape the gridlocked hellhole of Southern California, it has some of the finest roads anywhere on the planet. The road ascends and descends with a mix of sweepers and third-gear corners that keep the Katana in the ­generously broad sweet spot of its rev range. Trail-braking hard into downhill hairpins, the front suspension doesn’t offer the last word in hard-braking support, too quickly compressing through its travel and skipping off small bumps, ultimately making the front-end feel a bit vague. Getting on the gas to take load off the front alleviates much of the issue, however, so the Katana tracks well midcorner and through the exit. Otherwise, the fully adjustable 43mm KYB front and rear shocks (adjustable for pre-load and rebound) are compliant over rough surfaces. With its Brembo radial monoblock caliper (front) and Nissin (rear), the Katana recorded a 60-to-zero braking test in 133.9 feet, comparable to the 136.8 feet recorded by the Honda CB1000R that we tested in 2019. Unfortunately, the Katana’s system doesn’t offer the same feedback through the lever as higher-spec items. In terms of handling, Michael Gilbert, CW’s ­resident MotoAmerica racer, notes: “The Katana requires a degree of physical exertion to change directions in side-to-side transitions, but once settled into the corner, its chassis is impeccably planted, confidently carving corners with the prowess of a sportbike.” It’s worth remembering that the Katana doesn’t disguise its rotating mass with a fancy counter-rotating crank like many of today’s cutting-edge literbikes. The K5 engine is, after all, essentially a 15-year-old unit. Polarizing style belied the original’s conventional underpinnings. (Cycle World Archives/)But that 15-year-old engine is the Katana’s party piece. The GSX-R1000 K5 is one of the most notorious motorcycles of the halcyon age of race-replica superbikes. Valentino Rossi describes his 500cc grand prix motorcycle as a “bike beyond all reason.” Mere mortals would make a similar remark about the GSX-R1000 K5. It was an absolute gorilla and delivered all its power with not one rider aid, except excellent throttle response and predictable, abundant torque. Suffice it to say, there’s ample reason BMW studied the K5 powerplant when building its first S1000RR superbike. Subsequent Gixxers got heavier as emissions standards grew stricter, and power modes and other electronics were added, so in many regards, the K5 represents perhaps the purest evolution of raw GSX-R. The 1982 Katana’s dash had dial needles facing in opposite directions. (Cycle World Archives/)Like a 15-year-old barrel of bourbon that’s lost more heavenly fluid to the angels than its seven-year-old counterpart, the Katana motor has lost a few ponies and revs in its revamped role as a roadbike. Suzuki chief engineer Satoru Terada emphasizes: “We didn’t want to unnecessarily pursue peak power, but instead focus on pursuing the ideal characteristic for streetfighter models that correspond to Katana’s positioning in the market.” On our dyno, the Katana produces 139.6 horsepower at 10,100 rpm and 76.3 pound-feet of torque at 9,200 rpm. The last time we put a K5 on the dyno, it produced 156.9 horsepower at 11,500 rpm and 78.9 pound-feet of torque at 8,600 rpm. So, while the Katana’s unit isn’t the uncut original, it’s still a high-proof swig of Japanese firewater. And to hear it is to know it. That muscular, classic-four rumble is Suzuki’s leitmotif—all induction howl and on-the-pipe savagery. The exhaust note sounds bassy and full by 2020 standards. Accessory switches and choke knob are integrated into sidecover. (Cycle World Archive/)At the first touch of the throttle, it’s all systems go. While on-off throttle isn’t abrupt—the ’16 GSX-S’s fueling niggles were resolved with ignition and EFI updates in 2018 and 2019—the throttle is like a hair trigger, requiring the most delicate touch. On the gas, the motor has that frenetic yet buttery power delivery characteristic of a 1,000cc four. There’s so much grunt down low that taking corners in too high a gear isn’t really a thing. But hit 7,000 rpm and the motor comes to life, resurrecting Y2K5 images of our wayward, wheel-lofting youth. Where the K5 was searingly fast—just fast as hell—the Katana is simply fast. Fast as purgatory maybe. Fast enough that it’s hard to restrain yourself from being a glutton of vroom, gorging yourself on whopping helpings of horsepower and noise. As the poet William Blake said, “Those who restrain desire do so because theirs is weak enough to be restrained”—perhaps not a great excuse in the event a cop pings you in a moment of unrestrained throttle twisting, but still. 2020 Suzuki Katana (Jeff Allen /)On a Katana, desire is measured by quarter-mile trap speeds. At our testing facility, it set a time of 10.86 seconds at 133.3 mph and went from zero to 60 in 3.2 seconds—that’s not too far off times set by current superbikes. With an excess of exuberance, we found the Katana delivered an average of 43 mpg. With its diminutive 3.2-gallon tank, expect to start getting nervous when the tripmeter hits just 100 miles. The 2020 Katana’s character lines reference the original’s, but the designers took liberties with them in order to give the motorcycle a 21st-century identity. (Jeff Allen /)The Katana has a slipper/assist clutch that’s as light as can be and barely needs to be touched on upshifts. While a quickshifter would be nice, the gearbox is so lovely, it doesn’t seem a glaring omission. Besides, blipping the throttle on downshifts provides a period-correct pleasure. It’s easy to find neutral at a standstill; the shift lever feels light, and the close-ratio box just begs to be frequently exploited for the pure joy of it. That being said, at $13,499, the Katana isn’t ­particularly well-equipped. It has nonswitchable ABS and three-­level traction control (plus off), but neither are lean-angle-sensitive. The LCD dash is a bit outmoded, and several of our testers found it difficult to navigate. It also lacks the brightness we’ve grown accustomed to with TFT displays. The 2020 Katana is a self-assured roadster powered by a version of one of the all-time-great inline-fours. (Jeff Allen /)There’s no doubt aesthetics are an important part of the Katana’s formula. Consequently, pride of ownership is of great value here, so the stakes are high when it comes to fit-and-finish. Unfortunately, the Katana falls a bit short. Welds on the aluminum frame are inelegant-looking compared with those of the K5, which were as precise and delicate as the piping on a wedding cake. Likewise, the plastic tank cover has a thin seam discernible through the paint, and the seat-cover material has an odd latex feel. Gilbert says the whole package feels like a ­15-year-old motorcycle. That’s not necessarily a bad thing. In its homage to 1981, Suzuki ended up with an ode to 2005. But there’s more to it than that. For 2020, Suzuki took a sportbike and turned it into a standard. In the ’80s, it took a standard and turned it into a sportbike. It illustrates the vast evolution of the motorcycle (and of market demands) in 40 short years. It has the right name, the look, and the motor—did we mention the motor?—to do Etsuo Yokouchi proud. (Jeff Allen /)The original Katana marks a turning point in that evolution, a distinct moment in a two-wheeled world on the cusp of change. Yokouchi’s Katana looks radical to this day, but it was not his revolution. That would be the 1985 GSX-R750, the bike that made him the father of the modern sportbike. While the Katana’s air-cooled engine and steel-tube double-cradle frame were mechanically conventional, the GSX-R was revolutionary in practically every way. In retrospect, the original Katana is a transition bike, a one-way bridge between the sit-up superbikes of the 1970s and race-replica R sportbikes ushered in by the first GSX-R. The 2020 Katana is so special because it transports its rider back and forth between both of those worlds. It’s a mashup of the evolution of motorcycling, the missing link between generations. It bends the line between the GS1100, GS1000S Katana, GSX-R750, and GSX-R1000 K5, transforming it into a closed loop. The challenge with building a retro bike—especially one that reinterprets an icon that was all about looking ahead—is it risks coming out retrograde, not retrospective. But the Katana’s unique blend of performance, style, and authentically Japanese sensibilities makes it a true retrospective that honors not just its namesake, but also Suzuki’s storied history and pursuit of GS excellence. 2020 Suzuki Katana Type Liquid-cooled inline-four Displacement 999cc Bore x Stroke 73.4 x 59.0mm Compression Ratio 12.2:1 Valvetrain DOHC, 4 valves/cylinder Induction (4) 44mm throttle bodies Final Drive 6-speed/chain Front Suspension KYB 43mm fork, fully adjustable; 4.7-in. travel Rear Suspension KYB monoshock, adjustable rebound, spring preload; 5.1-in. travel Front Tire Dunlop Roadsport 2 120/70-17 Rear Tire Dunlop Roadsport 2 190/50-17 Rake / Trail 25.0°/3.9 in. Wheelbase 57.6 in. Seat Height 33.2 in. Fuel Capacity 3.2 gal. Dry Weight 456 lb. Horsepower 139.6 hp @ 10,100 rpm Torque 76.3 lb.-ft. @ 9,200 rpm Fuel Consumption 43 mpg Quarter-Mile 10.86 sec. @ 133.3 mph 0–30 1.64 sec. 0–60 3.20 sec. 0–100 6.04 sec. Top-Gear Roll on 40–60 2.54 sec. Top-Gear Roll on 60–80 2.66 sec. Braking 30–0 33.7 ft. Braking 60–0 133.9 ft. Price $13,499 Source

2020 Husqvarna FE 350 (Husqvana/)The 2020 Husqvarna FE 350 is a 350cc four-stroke enduro bike aimed at trail riders looking for a 50-state emissions legal off-road motorcycle. With its midlevel displacement, the FE 350 is designed to offer a 450-like power-to-weight ratio, while maintaining the light and agile feel of a 250. Although it shares many of the same components as the 2020 KTM 350 XCF-W of which it’s based off of, the FE 350 features shock linkage, whereas the 350 XCF-W is equipped with a Progressive Damping System (PDS) shock. 2020 Husqvarna FE 350 (Husqvana/)2020 Husqvarna FE 350 Reviews, Comparisons, And Competition In our review of the FE 350, test rider Allan Brown explained why the FE 350 is best suited to a beginner or intermediate rider in stock trim and that it could suit a higher-level rider with some aftermarket modifications: “The 2020 Husqvarna FE 350 is very easy to ride and it doesn’t feel intimidating when you start out on it. As your skills improve, the bike has the potential to improve with you. The suspension could easily be revalved and the engine is quietly waiting for someone to unleash its potential.” Sign up here to receive our newsletters. Get the latest in motorcycle reviews, tests, and industry news, subscribe here for our YouTube channel. Before we hit the trails on the 2020 Husqvarna FE 350, we ran it on our in-house dyno. As far as competition in the four-stroke enduro bike segment, the FE 350’s two closest rivals would be the 2020 KTM 350 XCF-W and 2020 Yamaha WR250F. At $10,499, the FE 350 costs the same as the 350 XCF-W and $1,900 more than the WR250F. 2020 Husqvarna FE 350 (Husqvana/)Husqvarna FE 350 Updates For 2020 Although there technically was an FE 350 model in 2019, it was a dual sport model, and Husqvarna renamed its 350cc four-stroke street-legal dirt bike to “FE 350s” for 2020. After discontinuing its 350cc four-stroke enduro bike in 2017, Husqvarna brought it back in 2020 under the same name of FE 350. With that, the FE 350 has changed significantly since it was last on the market in 2016. In its reemergence among Husqvarna’s lineup, the FE 350 features a completely new chassis, new suspension components, and a new engine. 2020 Husqvarna FE 350 Claimed Specifications Price: $10,499 Engine: Liquid-cooled DOHC single-cylinder Displacement: 350cc Bore x Stroke: 88.0 x 57.5mm Horsepower: N/A Torque: N/A Transmission: 6-speed Final Drive: Chain Seat Height: 37.4 in. Rake: 26.5° Trail: N/A Front Suspension: 48mm inverted fork, fully adjustable; 11.8-in. travel Rear Suspension: Fully adjustable; 11.8-in. travel Front Tire: 80/100-21 Rear Tire: 110/100-18 Wheelbase: 58.5 in. Fuel Capacity: 2.2 gal. Claimed Wet Weight: 236 lb. Cycle World Tested Specifications Seat Height: 36.6 in. Wet Weight: 251 lb. Rear-Wheel Horsepower: 36.9 hp @ 9,400 rpm Rear-Wheel Torque: 21.7 lb.-ft. @ 8,400 rpm Source

A half-century of development kept the XR750 at the front of the pack for most of that time. Now with the Indian FTR750 winning in dominating fashion and Harley-Davidson campaigning the XG750, could the XR ever win again? (Harley-Davidson /)The previous two installments of this 50th anniversary series centered on the genesis and development of Harley-Davidson’s XR750, as well as the outsized contributions to its glorious history made by three titanic talents in Jay Springsteen, Scott Parker, and Chris Carr. However, while those stories of the XR span from the ’60s into the new millennium and effectively defined the careers of perhaps the three greatest riders American Flat Track has ever known, it would be a great disservice to the bike to suggest its history ends there. In truth, the legacy of the XR750 transcends far beyond even those eras, heroes, and the sport of dirt track racing entirely. Addressing that last point first, we could argue that no two-wheeled icon and their equipment have achieved the same sort of celebrity or has been etched so permanently into the public consciousness as daredevil Evel Knievel and his fleet of red-white-and-blue XR750s. What child of the ’70s didn’t have at least one Evel Knievel XR750 toy? Evel Knievel brought the XR750 into nearly every American home. (Motorcyclist Archives/)And the XR didn’t only succeed on dirt or in the air. Cal Rayborn was the hero of the ’72 Transatlantic Match Races on a roadrace-spec Iron XR750 TT, and then gave the Aluminum XR its only two GNC roadrace victories later that year at Indianapolis Raceway Park and Laguna Seca. Mark Brelsford actually earned the first (and only other) GNC roadrace win for the platform in ’71 at Loudon on an Iron XR. A couple of years later, Brelsford’s Number 1 Aluminum XR750 TT went up in flames (along with his hopes of defending the Grand National Championship) in a dramatic crash at Daytona International Speedway. A decade later, that same destroyed bike was pulled from purgatory and re-forged into a pumped-up 1,000cc XR-based racer that promptly won the Battle of the Twins race at Daytona with Springsteen at the controls. The resurrected machine was then dubbed “Lucifer’s Hammer,” wrenched by famed H-D tuner Don Tilley, and wielded by Gene Church. The pairing went on to claim the AMA BOTT crown for three years running from ’84–’86. But even when taking only the XR’s flat track accomplishments into consideration, there’s so much more to the story. While Springsteen, Parker, and Carr did combine for an astonishing 183 main event victories and 19 Grand National Championship wins, simple arithmetic tells you that still leaves an additional 319 wins and 18 GNCs on the docket. Digging deeper, 55 riders other than the Big Three won races on the XR750, and 11 of those 55 earned at least one Grand National Championship aboard it. Over 50 years, the Harley-Davidson XR750 has captured 502 wins and 37 Grand National Championships. Is a 503rd win possible? (Harley-Davidson /)The full story of XR750’s reign also happens to be very much a modern one. Of those 18 non-Springsteen/Parker/Carr titles, the bulk of them came following Carr’s final Grand National Championship in 2005. It’s only due to recency bias that it feels like the recent history of American Flat track can be summed up as the rise of the Kawasakis—culminating in Bryan Smith’s 2016 crown—followed one year later by both Harley-Davidson’s pivot to the XR750’s successor, the production-based XG750R, and the return of Indian Motorcycle with its purpose-built XR killer, the FTR750. The reality is the XR750 played as the backdrop for all of those monumental developments, leading ubiquity to instantly seeming like antiquity. The all-guns-blazing reemergence of Indian Motorcycle, in particular, had a massive impact on the sport. Indian followed the blueprint utilized so effectively by Honda in the mid-’80s with its once-dominant RS750 and perfected it with the added edge of three decades of technological advancements to call upon. 2000 Grand National Champion Joe Kopp was brought onboard in a testing and developmental role in 2016 and found the FTR to be instantly familiar following a long and successful career campaigning XRs. Indian’s FTR750 has dominated since its arrival. (Indian Motorcycle /)“It has a purpose-built engine like in the XR750… I wouldn't say they copied it, but there are a lot of the same things, like a four-speed transmission and big heavy flywheels on the crank…a lot of similarities,” Kopp said. “The only thing that's really different, I'd say, is the modern technology with fuel injection and ignition timing and stuff like that.” Kopp gave the all-new FTR750 its AFT debut in a shakedown ride at the 2016 season finale ahead of its impending full-scale 2017 campaign. The 47-year-old turned heads with his seventh-place run in the Indian’s maiden performance at the Santa Rosa Mile, but that effort was largely overshadowed by Brad Baker, who gave the XR750 a proper send-off by winning the machine’s final outing as a full-factory racebike in blowout fashion. There was no denying Indian Motorcycle the spotlight the very next day however, when it enacted the next stage of its plan for dirt track domination. Yamaha had beaten H-D and its superior XR750 in the ’70s thanks primarily to the singular brilliance of Kenny Roberts. Honda had then done the same with its outstanding RS750 and a pair of superstars in Ricky Graham and Bubba Shobert in the ’80s. Indian took it one step further. It hired the series’ three most recent Grand National Champions, Smith, Baker, and perhaps the biggest catch of all, Jared Mees, assembling its own version of the “Wrecking Crew.” By that point, Mees had been well on his way to expanding the exclusive “Titans of the XR750” club to four. Before signing with Indian, he’d already claimed four Grand National Championships on the XR and ranked seventh in the machine’s history with 20 victories to his credit. Jared Mees took four GNC titles on the XR750. (Dave Hoenig/)Since joining Indian, Mees has only accelerated his assault on the record books, storming past Springsteen in all-time wins (now with 48 to Springer’s 43, trailing only Parker’s 94 and Carr’s 78). And as a result, the perception of his place has likely been forever altered; the same way Ricky Graham, who took the 1982 Grand National Championship on an XR750, is best remembered as the master of the RS750, Mees seems destined to be most closely aligned with the FTR750 after his racing days are done. Mees clinched the FTR’s first title in its opening attempt with two races still remaining in the 2017 season. With the championship already locked up, he entered the penultimate race of the year in Fort Worth, Texas, riding a run of five consecutive oval wins—a streak that likely would have been eight if not for some uncharacteristic start line mishaps at Lima Half-Mile. Similar to the situation that helped pave the way for Honda’s overwhelming success in the ’80s, Indian’s ascent transpired while H-D’s factory race program was most vulnerable, deep in the development phase of the new XG platform. Yet, despite being “officially” left behind, the XR750 still had some fight left in it yet. Privateer Jeffrey Carver Jr., showed up for the Lone Star Half-Mile in a van with just crew chief Ben Evans in tow and a single XR750. Jeffrey Carver Jr. earned the XR750 its 502nd win. (Scott Hunter, AFT/)“We actually broke our Kawi the week before,” Carver explained. “We thought we were going to have to ride the backup, but its motor wasn't as good. We were sitting there at the shop, and Gary Goodwin was there. He had given us an XR, and he was like, 'What about that bike?' “ 'I don't know… We’d need two of them.' “ ‘Welp, you’ve got one good one and that's all you need. Imagine being the last one to ever win a race on an XR750.’ “Man, I was so fired up. I'm not one to say, ‘Hey, we're going to go to this race and win.’ I just let the energy play itself out.” Even with a field stacked with Indian FTR750s, H-D XG750s, Kawasaki Ninja 650s, and Yamaha FZ-07s, nothing stood a chance against Carver and that XR750 on a slick Texas Motor Speedway surface. “When you’re on a track, the XR delivers the horsepower down to the track. When it gets slippery, the XR just has the characteristics to really hook up to the ground,” nine-time GNC winner Parker said. “The Yamahas struggled at that in their era and the Hondas struggled at that for a period of time too. That's the big thing. It will hook up to the racetrack where the other bikes would struggle trying to get tires to hook up onto the dirt.” Mees just couldn’t catch Carver in Texas as the privateer took the last win for the XR750. (Scott Hunter, AFT /)“I had been close—podiums and running up front,” Carver said. “At the beginning of that year, I was going to quit and maybe try to find something else to do, at least part time. I didn't even know if I was going to the West Coast for the races. To come out and have that drive and that grit, I didn't care, you had the factory Harleys, the factory Indians. To be able to go there and win—it was just amazing. I just had this determination in my eyes that day.” Only one rider could so much as keep Carver in sight that evening: Mees, who finished more than a second and a half back in second. “I tried so hard to gain on him; I couldn't bridge the gap,” Mees admitted. Carver's mechanic Ben Evans proudly celebrates the victory. (Scott Hunter, AFT /)As the weekends and seasons continue to add up, Carver’s underdog victory in Texas seems more and more likely to go down as the XR750’s last hurrah. He did wheel it back out at the Atlanta Short Track early in 2018 to score another podium finish, but the series has only further fallen into Indian’s clutches. Since Carver’s upset, the FTR750 has taken 34 out of a possible 37 main event triumphs. Meanwhile, while improving, Harley’s factory XG750R racebike is still looking for its first. While impossible to predict at the time, Carver did give the XR750 one final bragging right. The FTR750 closed out the decade with 47 wins. And thanks to Carver, the XR750 ended the 2010s with 48. Granted, the FTR amassed those wins in much less time. The XR750 is now largely absent from AFT competition. Danny Eslick did manage to score points on it last season at Lima, serving as a fleeting reminder of the potential of its continued relevance. “Sure, one hasn't won since 2017,” Kopp said. “But we really haven't seen them much on the track since then with a real capable rider. Honestly, there are some tracks—if I was 20 or 30 years younger—I would still choose the XR750 at times over an Indian, honestly.” Kopp in the midst of his 2000 championship hunt. (Dave Hoenig/)Asked if he believed it could still win, Parker said, “I do. I really do. Why would you not expect it? My career ended in 2000. Twenty years later they kept tweaking it here, tweaking it there. You can have a 1,000-horsepower motorcycle, but you've still got to hook it up to the ground, and that's the key issue. Just because you've got a faster, more powerful bike, doesn't mean you can go faster around a circle.” “I know you could still win on that thing,” Kopp added. “There are certain tracks where it’s favorable in my mind. A slick clay car track—the slicker the better for that thing—and with a more rounded straightaway, it would be hard to beat still. I’m confident in that.” The XR750 has become widely considered to be the most successful racebike in motorcycle racing history, perhaps the greatest vehicle in motorsports history. Is there even any competition? What other machine boasts a half-century reign spent transforming talents into heroes and heroes into legends? And best of all, this legacy might not yet be fully written. Source

2020 Yamaha XT250 (Yamaha /)Of Yamaha’s three dual sport bikes, and one of those is the simplistic XT250. Although it is designed more for the casual rider, the XT250 packs a reliable punch. It is powered by a 249cc, air-cooled, four-stroke engine. The suspension duties are handled by a nonadjustable 35mm conventional fork, while the shock is adjustable for preload and rebound damping. With its estimated fuel mileage of 76 mpg and its 2.6-gallon fuel tank (2.4-gallon for the California model), the XT250 can cover a decent amount of ground on a single fill-up. 2020 Yamaha XT250 (Yamaha /)2020 Yamaha XT250 Reviews, Comparisons, And Competition Some competitors for the Yamaha XT250 would include the Kawasaki KLX230, Honda CRF250L, and Kawasaki KLX250. At $5,199, the XT250 is $600 more than the KLX230, the same price as the CRF250L, and $200 less than the KLX250. Yamaha XT250 Updates For 2020 If you liked everything about the 2019 Yamaha XT250, you’re in luck because the 2020 model is exactly the same. 2020 Yamaha XT250 (Yamaha /)2020 Yamaha XT250 Claimed Specifications Price: $5,199 Engine: Air-cooled SOHC single-cylinder Displacement: 249cc Bore x Stroke: 74.0 x 58.0mm Horsepower: N/A Torque: N/A Transmission: 5-speed Final Drive: Chain Seat Height: 31.9 in. Rake: 26.4° Trail: 4.2 in. Front Suspension: 35mm conventional fork, nonadjustable; 8.9-in. travel Rear Suspension: Preload and rebound damping adjustable; 7.1-in. travel Front Tire: 2.75-21 Rear Tire: 120/80-18 Wheelbase: 53.5 in. Fuel Capacity: 2.6 gal., 2.4 gal. (CA model) Claimed Wet Weight: 291 lb. Source

2020 Husqvarna FX 450 (Husqvarna/)The largest-displacement off-road competition motorcycle from Husqvarna is the FX 450. Although it shares many of its components with the FC 450 motocross bike, the FX 450’s softer suspension settings, larger 2.25-gallon fuel tank, 18-inch rear wheel, kickstand, and Dunlop Geomax AT81 tires make it more suitable for cross-country racing. 2020 Husqvarna FX 450 Reviews, Comparisons, And Competition Since it was first introduced in 2017, we have tested, dyno’d, and compared the FX 450 against others in the 450cc four-stroke cross-country motorcycle segment. In our review of the 2020 model, test rider Allan Brown had plenty of good things to say about the bike: “The FX 450’s strengths are plenty of smooth and usable power, precise handling, a lightweight feeling, and great ergonomics.” 2020 Husqvarna FX 450 (Husqvarna/)Its competitors include the 2020 KTM 450 XC-F, 2020 Yamaha YZ450FX, and 2020 Honda CRF450RX. With its suggested retail price of $10,699, the FX 450 costs $100 more than the 450 XC-F, $1,100 more than the YZ450FX, and $1,000 more than the CRF450RX. Husqvarna FX 450 Updates For 2020 New graphics are the only change the FX 450 received for 2020, but the bike was heavily updated the year before with a stiffer frame, updated suspension settings, and a shorter and lighter cylinder head. 2020 Husqvarna FX 450 (Husqvarna/)2020 Husqvarna FX 450 Claimed Specifications Price: $10,699 Engine: Liquid-cooled SOHC single-cylinder Displacement: 450cc Bore x Stroke: 95.0 x 63.4mm Horsepower: N/A Torque: N/A Transmission: 5-speed Final Drive: Chain Seat Height: 37.4 in. Rake: 26.1° Trail: N/A Front Suspension: 48mm inverted fork, fully adjustable; 12.2-in. travel Rear Suspension: Fully adjustable; 11.8-in. travel Front Suspension: 48mm inverted fork, fully adjustable; 12.2-in. travel Rear Suspension: Fully adjustable; 11.8-in. travel Front Tire: 90/90-21 Rear Tire: 110/100-18 Wheelbase: 58.5 in. Fuel Capacity: 2.25 gal. Claimed Dry Weight: 223 lb. Cycle World Tested Specifications Seat Height: 37.2 in. Wet Weight: 239 lb. Rear-Wheel Horsepower: 51.1 hp @ 10,000 rpm Rear-Wheel Torque: 32.2 lb.-ft. @ 7,600 rpm Source

2020 Yamaha Star Venture (Yamaha /)When Yamaha’s big tourer made its debut in 2018, the marquee item on the all-new, freshly designed Star Venture was the air-cooled V-twin engine, a change from the V-4 arrangement of previous models. But that massive 113ci (1,854cc) mill is designed specifically for long-distance touring and the counterbalanced engine is rubber-mounted in an entirely new chassis, while modern electronics get packed into every nook and cranny of this dresser. All the cushy touring amenities are back as well, like cruise control, traction control, linked ABS, Sure-Park parking assist, infotainment, ride modes, an adjustable backrest, and more. 2020 Yamaha Star Venture (Yamaha /)2020 Yamaha Star Venture Reviews, Comparisons, And Competition In his First Ride Review of the Venture (with his wife aboard), Joe Gustafson remarked, “The new motor has torque everywhere, stump-pulling, smooth-as-silk torquey goodness. Even two-up and fully laden, the most the bike required was two downshifts on the steepest of inclines.” Hardcore tourers and happy couples alike will be drawn to this luxury tourer for all those reasons, and those folks will be comparing it to competitors like the Honda Gold Wing Tour, BMW’s K 1600 Grand America, and perhaps the more retrofied Indian Roadmaster. 2020 Yamaha Star Venture (Yamaha /)Yamaha Star Venture Updates For 2020 There are exactly zero changes for 2020, including the price. Impact Blue joins Granite Gray as a new color option, however. The Transcontinental Option Package upgrade adds supplemental LED fog lamps, additional storage for the passenger, and an alarmed security system. 2020 Yamaha Star Venture Claimed Specifications Price $24,999–$26,999 Engine Air-cooled V-twin; 4 valves/cyl. Displacement 1,854cc Bore x Stroke 100.0 x 118.0mm Horsepower N/A Torque 53.8 lb.-ft. @ 3,750 rpm Transmission 6-speed; multiplate assist and slipper clutch Final Drive Belt Seat Height 27.4 in. Rake 31.0° Trail 5.7 in. Front Suspension 46mm telescopic fork; 5.1-in. travel Rear Suspension Single preload adjustable shock; 4.3-in. travel Front Tire 130/70R-18 Rear Tire 200/55R-16 Wheelbase 67.3 in. Fuel Capacity 6.6 gal. Claimed Wet Weight 957 lb. Source

CFMoto’s new 1250J police model is said to output 140 hp, making it the most powerful motorcycle to come out of China. (CFMoto/)Back in late 2017, the Chinese firm CFMoto surprised the motorcycle world with a spectacular concept bike—the awkwardly named V.02 NK—that demonstrated what it believed lay in its future. Now the chances of the concept becoming reality have taken a huge step forward as its engine has hit the streets in China as the basis for the nation’s latest police bike. When it showed the V.02NK, CFMoto offered few technical details, only suggesting a 1,000cc-plus capacity, but it quickly emerged that the engine was a development of KTM’s LC8 V-twin. CFMoto is already KTM’s partner firm in China; it builds the 200 and 390 Duke models and is due to start manufacturing the 790 Duke and 790 Adventure in a purpose-made plant later this year. However, it hasn’t simply borrowed the existing LC8 engine in either current 1,301cc “1290” form or its earlier iterations. Instead CFMoto has used the basics of the engine to create a purpose-made 1,279cc V-twin that’s certified to make 140 hp in the new CF1250J police bike, which is also destined to be offered as a BMW-rivaling tourer. That power figure makes it easily the most powerful motorcycle to emerge from China, and one that’s on par with similarly sized tourers from European firms like BMW in terms of performance. Although in current form it wears police accessories, the CF1250J could easily be the platform for a civilian spin-off. (CFMoto/)The CF1250J While the new CF1250J police bike doesn’t look much like the V.02NK concept, its engine is externally virtually identical. Although the layout and general design comes via KTM, the engine’s cases, cylinders, and heads are all noticeably different from any KTM version of the engine and its internal measurements are also unique to CFMoto. Although the firm has yet to make any official statement about the CF1250J, its specifications are revealed in Chinese type-approval documents, which confirm that it makes 140 hp and weighs 655 pounds, with a top speed of 149 mph. CFMoto’s V.02NK concept from 2017 used the basics of KTM’s LC8 engine to create a purpose-made V-twin. (CFMoto/)The CF1250J’s existence was first revealed in design patents last year, but now it has hit the streets in real-world police use, showing that its development period is complete and production is underway. Given the vast size of China’s police and security services, if CFMoto has secured the contract to supply the next generation of official bikes, it’s a guarantee of thousands of sales—and enough to largely offset the considerable R&D expense of developing the bike. CFMoto has previously followed the same pattern with its existing 650cc parallel-twin bikes. A police-spec touring version led the way, becoming the standard motorcycle of China’s government forces, and it led to naked, adventure-sport, and sport-touring derivatives to be sold to the general public. What we’ve seen of the bike so far flies in the face of stereotypes of substandard, derivative Chinese motorcycles. The firm outsources its styling to Kiska Design, which is part-owned by KTM’s parent firm Pierer Mobility and responsible for the visuals of all KTM’s current offerings. CFMoto has also turned to the West when it comes to parts and technology, outfitting some models with Brembo brakes and Bosch electronics. And on the subject of electronics, videos of the new police bikes on Chinese social media reveal the biggest TFT color instrument display that we’ve yet seen on two wheels. Production is underway for the Brembo-and-Bosch-equipped CF1250J. It’s destined for use by Chinese police and security services. (CFMoto/)What Does That Mean For The V.02NK? Although the concept bike isn’t likely to reach production exactly as it appeared in 2017, the fact that the engine is ready for the limelight means that something similar is sure to be on CFMoto’s mind. In the firm’s current streetbike range, the naked 650NK is the mainstay model, and that means an unfaired 1250NK built around the new 1,279cc twin is likely to be the first civilian spin-off from the CF1250J. The police bike’s chassis isn’t easy to make out thanks to its all-enveloping bodywork, but design patents for the machine show a tubular steel frame very similar to that used on KTM’s old-generation (2014–2019) Super Duke. That means it could easily be fitted with a single-sided swingarm, as used on the Super Duke and the V.02NK concept, and wrapped in stripped-back bodywork. We likely won’t see the V.02NK concept reach production in this form, though a CFMoto naked model based on the new 1,279cc engine is likely. (CFMoto/)It’s clear that some elements of the V.02NK have been dropped. The concept featured an underseat radiator, for instance, whereas the CF1250J has a conventional front-mounted unit. The unusual rear shock mounting of the concept, which avoided a conventional upper shock bracket on the frame, is also unlikely to reach production. Since CFMoto already has a worldwide dealer network (although limited in the US), offering ATVs and side-by-sides as well as motorcycles, any bike it develops isn’t likely to be kept for the Chinese market. Whether the firm’s deal with KTM puts any limits on the styles of bike it can create around the new engine or the markets it can sell in remains unknown, but if it follows the pattern set in the existing 650cc range, we should expect the new V-twin to go into a “1250NK” naked bike, surely inspired by the V.02NK, and then into a street-oriented adventure-sport “MT” model and a sport-touring “GT.” Source

A combination of simplicity and ruthlessness is what makes super-naked motorcycles so tempting. They blend the lines of edgy and utilitarian, usually in the form of a bare-bones open-class supersport machine with a meaty powerband and top-tier electronics, but with a (more) comfortable riding position. It’s a category where manufacturers can express their true potential on platforms attractive to mortals. And not to mention, super nakeds are just wickedly entertaining. So it's no surprise then that Ducati stripped most of the bodywork off its premium superbike offering, the Panigale V4, adjusted the ergonomics package, and cut it loose as the 2020 Ducati Streetfighter V4 and V4 S. The Ducati Streetfighter enters the market as a bareboned, stripped down Panigale V4 with revised ergonomics and engine mapping. (Jeff Allen /)Like the Panigale on which it is based, the Streetfighter is powered by the 1,103cc Desmosedici Stradale 90-degree V-4 engine, but tuned with dedicated engine mapping and given shorter final drive gearing (via subtraction of one tooth on the countershaft sprocket and addition of one tooth on the rear). The result of the revisions is a powerplant that Ducati says is worthy of 208 hp at 12,750 rpm and 90.4 pound-feet of torque at 11,500 rpm—just shy of the 214 hp claimed for the Panigale. But considering the last Panigale V4 we had on our in-house dyno belted out 186 hp, presume the Streetfighter to rip high 170s to low 180s at the rear wheel. Heck, Ducati’s World Superbike homologation-special Panigale V4 R ripped 203 hp on our dyno. It’s proof of how remarkable the Streetfighter’s powerplant is in stock form, and that there is serious potential. Absolute confidence in the Streetfighter V4 allowed traction- and wheelie-control settings to be minimized. (Jeff Allen /)It's a delightful engine to ride at any pace, but a monster if you want it to be. Ducati struck gold in balancing its power characteristics, finding an impressive medium between rowdy performance and rideability—even more so than the Panigale. At first touch of the throttle, the Streetfighter offers a crisp and tractable power delivery as it comfortably transfers weight rearward for supreme confidence at corner exit. But hit the 7,000 rpm mark, and you’ll witness the V4 in all its glory as it lofts the front end skyward and sends your glutes into the rear cowling under hard acceleration. The Streetfighter’s electronic rider aid suite is accessed via this 5-inch TFT display. (Jeff Allen /)The engine is so tractable that I preferred deactivating a number of the Streetfighter’s rider aids, including the Ducati Traction Control (DTC) EVO 2 system—interestingly derived from Ducati’s Desmosedici GP18 MotoGP racer and employed on the superbike homologation-special Panigale V4 R—and Ducati Wheelie Control (DWC) EVO to experience the bike’s raw capability and maximum fun factor. And while I enjoyed riding it raw, so to speak, the rider aids are superb. Toggling to level 3 of DTC and level 2 of DWC was my preferred means of electronic assistance for heavy-fisted riding, offering impressive corner exit speed and steadfast control, while allowing epic low-trajectory wheelie action. Radness. And heck, the Streetfighter even has a Ducati Power Launch (DPL) system for race starts and a lap timer function, which will rightfully prove their worth at the racetrack. A sticky set of Pirelli Diablo Rosso Corsa II tires glue the Streetfighter to the road with superb grip and feel. (Jeff Allen /)It has a chassis that will handle the racetrack too. Our testbike is the $23,995 V4 S model, with semi-active Öhlins NIX 30 fork and TTX 36 rear shock, Öhlins steering damper, and forged-aluminum Marchesini wheels, versus the fully adjustable, non-active 43mm Showa Big Piston Fork (BPF) and Sachs monoshock and cast-aluminum five-spoke wheels on the $19,995 standard model. The chassis is impeccably planted from midcorner onward, ridding itself of any sort of uneasiness and rear-end chassis pump that was familiar on the last Panigale I tested, while confidently ripping side-to-side transitions. Top-shelf Brembo Stylema brake calipers bring the Streetfighter to a quick halt, aided by seamless intervention of the Cornering ABS EVO system. (Jeff Allen /)Each of the Streetfighter’s Street, Sport, and Race ride modes has unique semi-active Öhlins Smart EC 2.0 parameters aimed at different riding habits and conditions. After systematically sampling each, I found Sport mode revealed the best compromise of support for aggressive riding and comfort on less-than-ideal road conditions, while quickly and unnoticeably compensating for changing tarmac. Race mode created a more visceral, harsh feeling in the suspension’s damping, and I see its place at a trackday, but as a current racer looking for lap-to-lap consistency and no surprises, I’d likely enter the fixed setting, in which damping characteristics are non-active. Being that the Streetfighter is aimed at a stripped-down, more comfortable version of the Panigale, Ducati revised footpeg placement and seat thickness, then fitted a one-piece motocross-style handlebar. The verdict? An ergonomic package worthy of all-day comfort. A long and low reach to the handlebar gives the Streetfighter an aggressive stance, but not so much to sacrifice leverage or create an awkward pressure at the wrists on back roads. That said, if the Streetfighter were mine, I’d roll the bar back just slightly to make around-town riding a little more comfortable and an easier reach for my average 5-foot-7 stature. It is an easy adjustment, and neat that you can quickly do this. Another plus for naked bikes. Even the saddle is pleasant, and only sent my glutes searching for relief roughly 250 miles into our day with the Streetfighter. The reduced amount of bodywork significantly reduces the intense heat buildup familiar on the Panigale. Heat control isn’t great on the Streetfighter, but due simply to the fact that there are more places it can escape, coping with it is no issue. The Ducati Streetfighter V4 puts the power to the ground and points the front wheel to the sky. (Jeff Allen /)There is no question that it is ridiculously fun and addicting to hammer it on this motorcycle—seriously, listen to that 90-degree V-4 sing just once and you’ll understand—but we pay the price in fuel mileage. In our limited time with the Streetfighter, average fuel consumption was only 27.6 mpg, and it drops even further the harder you hit it. In fact, we burned through the fuel tank’s 4.2 gallons in just 103.5 miles and were having so much fun we literally ran it dry! But it’s hard to be mad at the Streetfighter V4 S here, only ourselves. The very definition of this motorcycle’s purpose is to wring every bit of fun out of every ounce of fuel. We only had the Streetfighter V4 S for a short time, but we packed in a lot of miles. We weren’t able to do our normal instrumented testing or to dyno the bike, but we are working to secure a longer loan so we can perform a full test and live with the bike a bit longer. The cost of admission? The up-spec Streetfighter V4 S is priced at $23,995, while the base model sells for $19,995. (Jeff Allen /)This may be the most exquisite high-performance naked bike ever made. The Ducati Streetfighter V4 S combines high-level technical excellence with the sounds of a Mugello MotoGP race and puts that near your heart and in your garage for $24,000. In the world of exotic, high-performance Italian vehicles it’s an incredible value and remarkable experience. The sound alone is worth the price. The rest is just a bonus. It reminds us that high performance is a pleasure in its own right. The Streetfighter’s “biplane” wings are said to produce 74.9 pounds of downforce at a 186 mph—or 19.4 pounds at a more reasonable 93 mph speed. (Jeff Allen /)2020 Ducati Streetfighter V4 S Specs MSRP: $23,995 Engine: 1,103cc liquid-cooled V-4 Bore x Stroke: 81.0 x 53.5mm Transmission/Final Drive: 6-speed/chain Claimed Measured Horsepower: 208 hp @ 12,750 rpm Claimed Measure Torque: 90.4 lb.-ft. @ 11,500 rpm Fuel System: Electronic fuel injection Clutch: Wet, multiplate Frame: Aluminum alloy “front frame” Front Suspension: 43mm Öhlins NIX 30 w/ semi-active adjustable compression and rebound damping; 4.7-in. travel Rear Suspension: Öhlins TTX 36 w/ semi-active adjustable compression and rebound damping; 5.1-in. travel Front Brake: Brembo 4-piston Stylema Monoblock calipers, 330mm discs w/ Cornering ABS EVO Rear Brake: 2-piston caliper, 245mm disc w/ Cornering ABS EVO Wheels, Front/Rear: 3.50 x 17-in. / 6.00 x 17-in. Tires, Front/Rear: Pirelli Diablo Rosso Corsa II; 120/70-17 / 200/60-17 Rake/Trail: 24.5°/4.0 in. Wheelbase: 58.6 in. Seat Height: 33.3 in. Fuel Capacity: 4.2 gal. Cycle World Measured Wet Weight: 457 lb. Availability: Now Contact: ducati.com Source

These ChampSchool instructors share an important trait: 100-percent faith in the students’ ability to become an excellent rider—if they have the desire and the coaches put in the effort. Left to right: Scott Rybarik, Rob Cichielo, Kyle Wyman, Nick Ienatsch, Michael Henau, Chris Peris, Mark Schellinger. (4THERIDERS.COM/) cycleworld · Building Excellent Motorcycle RidersNick’s faith in rider development comes from what he’s seen, and Part 1 of his audio file speaks to future riders—riders who have lost the joy of riding and to the riding mentors and coaches. Source

After 25 years, the 916 (here shown in SPS form) offers a purity of design that continues to endure. (Ducati /)Maestro Massimo Tamburini’s first Ducati was the 1986 Paso, its sleek styling and perfectly balanced chassis making it the most “after 1950” motorcycle ever for the marque—and modern at the time by any standard. So, while the Paso is not the nearly mythological creature the Ducati 916 is, it remains a cornerstone in the evolution of motorcycle design. It was also key as Tamburini capitalized on the Paso’s lessons in aerodynamics, purity of design, and man-machine interface when it came time to embark on his greatest work. Around 1990, when Tamburini began working on this new project to harness the mighty Ducati 851–888 eight-valve Desmo V-twin, goals for the chassis were simple yet difficult: Build a long-lasting reference point by being the best-balanced Ducati chassis on the company’s shortest- ever wheelbase. Ducati’s 90-degree “L” twin does not help here because the lower cylinder forces the front wheel away from the center of gravity, and the eight-valve Desmo is even more problematic by being at least 1 inch bulkier than the SOHC 750 of the Paso. RELATED: Massimo Tamburini, 1943-2014 In addition, the 16-inch wheels and tires of the Paso were no longer in fashion, thus Tamburini could not count on the smaller diameter of the 130/60-16 front radial to pull the front end closer to the bike’s center of gravity. He designed the 916 chassis around a 55.5-inch wheelbase, marking these limits to scale on the drawing board, and then setting the side-view blueprint of the engine on top of it and progressively sliding it toward the front wheel. Whenever things came to a stop, he would extract two more millimeters from his immense creativeness to further bias more weight to the front. The last shot came by rotating the engine downward by 3 degrees and by daring an extreme front-end geometry: a 23.5-degree rake was used to reduce the amount of horizontal wheel recession when the fork was fully compressed. Tamburini was still a little short of that optimal 50-50 weight distribution (empty) with not one single millimeter to spare. The solution came by setting the battery aside the front cylinder, hidden under the fairing. The late Massimo Tamburini’s personal 916 is on display in Museo Ducati at the Bologna factory, its custom dash with only a tachometer and temperature gauge. (Ducati /)Short wheelbase and steep steering geometry generate twitchy steering response, but Tamburini adopted 30-millimeter-offset triple clamps for a 92.3-millimeter trail. When Massimo felt that his “balancing act” was finalized, he called me to proudly announce that he had obtained that 50-50 weight distribution on a Ducati spanning a 1,410-millimeter, or 55.5-inch, wheelbase. Knowing what designing an alternative chassis around the Ducati 90-degree V-twin means, I told Massimo that he might need to add one extra inch to the swingarm on the much more powerful SBK racer. A carbon-fiber clutch cover in black weave next to an either lightweight fiberglass or carbon-fiber fairing—no one remembers which! (Ducati /)Of course, Tamburini’s favorite steel-tubing trellis frame design made for a very elegant, lean structure, perfect for a rational and comfortable man-machine interface. On this lean structure, Tamburini set a compact tank that would naturally induce the rider to set their weight forward enough to keep the optimal 50-50 balance. The single-sided swingarm was Tamburini’s choice, and its structure was calculated resorting to the dear old sliderule—CAD was not there yet. Swingarm design was very complex, and the casting firm spent a lot of time and tons of bad words to get it right. Then came the magnesium superbike racer version (1 inch longer, as we had discussed), but the casting firm sharply rejected the order. Magnesium wheels, swingarm, Öhlins suspension spec’d, as maestro would. (Ducati /)Tamburini also played an obsessive role in defining fairing aerodynamics. How so? One rainy day, Tamburini donned his riding gear and set out in the pouring rain aboard one of the prototypes. An hour later he was back, completely drenched, and sharply ordered that the bike be left to dry untouched—he wanted to check the streaming marks left by the rain on the fairing to see where its design might create unwanted turbulence. That was Tamburini! In his quest for maximum neatness, the exhaust system had to be totally tucked in, not to interfere with the rider or his styling vision. Tamburini kept honing the 916 project in every single technical and styling detail for more than four years, working on at least three prototypes, with immense dedication, passion, and love. The Best Superbike in 1994’s Ten Best Bikes? You’re looking at it. “The most sensational superbike so far this decade.” Don Canet tests the original 916 in period-correct Bates custom leathers. (Bruno DePrato /)We know how it turned out. The Ducati 916 is an innovative, sleek, elegant superbike; it also was light, fast, easy to ride, stable, neutral, and immensely agile, with solid and precise steering response. It was designed by the wind. RELATED: Top 10 Sportbikes Of The 1990s Tamburini kept the last of his prototypes for himself. It is unique in that it was progressively fitted with special parts, like the magnesium superbike swingarm with large hub, and magnesium racing wheels. The fairing is very light, but nobody remembers if it is the experimental thin fiberglass or the carbon-fiber version. And only the tachometer is there. Tamburini would not need more. Godspeed Massimo, ciao! Your Ducati 916 is pure art, still unequalled. Source

This piston covered with oil does not occur in reality, but here symbolizes the fact that when adequate cooled and filtered oil of the correct viscosity and type is supplied to every point in the engine that needs it, life can be long and uneventful. (Jeff Allen /)In a celebrated case, a vertical shaft hydroelectric turbine ran continuously for 40 years without shutdown. When it was finally replaced, its thrust-bearing surfaces still bore the tool marks of their manufacture. How was that possible? It was because the bearing surfaces—one rotating, the other stationary—had never touched. They had been completely separated by a thin and continuously replaced film of oil. This is the ideal to which all surface friction in internal-combustion engines aspires: When surfaces are separated by a continuous oil film, wear from metal-to-metal contact is impossible. Why isn’t oil immediately squeezed out from between crank journals and bearings, between cam lobes and tappets, between pistons and piston rings, and the cylinders in which they slide? The internal friction of oil, called viscosity, strongly resists such squeezing out; it also allows the relative motion of the surfaces to continuously drag more oil between them. An engine’s oil pump does not generate the pressure that separates moving parts from each other. It is the motion of those parts, acting through the property of viscosity, that drags oil between them as fast as the applied load can squeeze it out. The amber color indicates the thin cylindrical oil film that separates the connecting rod’s big-end bearing from the crankpin. The piston, attached to the other end of the rod, is driven by high-pressure combustion gas. (Jeff Allen /)This can only work when an oil wedge is formed. Fresh oil is dragged in from the thick end of the wedge so forcibly that pressures of thousands of pounds per square inch have been measured in the loaded zones of crankshaft bearings. The wedge is formed as applied load pushes the journal slightly off-center within the bearing’s clearance. Oil is pumped into the bearing on its less-loaded side and is dragged into the loaded zone by the rotation of the journal. A piston and its rings tilt ever so slightly in the cylinder, forming an oil wedge between them. Engine-friction loss is mainly the force required to shear the oil films that separate its parts. As you reduce oil viscosity, friction loss drops, but oil films also become thinner—possibly thin enough that surface irregularities begin to touch each other. Viscosity is a compromise. An oil’s viscosity falls as its temperature rises, reducing its load-carrying ability. Hot zones such as the top of the cylinder, the top piston-ring groove, and exhaust-valve guides are therefore lubricated by hot oil that has lost much of its viscosity. To slow this high-temperature viscosity loss, so-called multigrade oils have been developed. Chemists found that some long-chain hydrocarbon molecules become more compact at low temperature—adding little or no viscosity—and extend or “unroll” at higher temperatures, which contributes some viscosity. This shows that load (in this drawing upward), applied to an oil-lubricated plain bearing, transforms the oil film into a crescent-shaped and extremely thin wedge that dynamically supports that load. The viscosity of the oil—its internal friction—causes it to be dragged by the rotation of the bearing into the very thin film in the loaded zone. There, the pressure generated by this dragging process can be thousands of pounds per square inch, and the minimum oil-film thickness is as little as 1.5 microns (0.00006 inch). (Jeff Allen /)When such molecules are added to base oils, they slow the rate of loss of viscosity with temperature, which is called the Viscosity Index. Thus, a multigrade 5W-30 oil is made from a 5W base oil—measured at zero degrees Fahrenheit—but the added long-chain molecules slow its viscosity loss to that of a 30-weight oil when at 212 degrees Fahrenheit. The oil does not become more viscous as it heats up—it just loses less of its viscosity. This allows use of engine oils thin enough to cold-start in winter, which retain enough viscosity when hot to do a good job of lubricating the hottest parts of a warmed-up engine. To handle the heat-driven sludging of oil when hot, detergents are added. These surround sludge particles, allowing them to be swept to the filter by oil flow. To protect oil molecules against the sludging effects of high-temperature oxidation, antioxidant is added. Most wear occurs during cold-start and warmup, when instead of full-film oil-wedge lubrication, mixed lubrication occurs—part oil film, part surface contact. To reduce damage, surface-active anti-wear additives are developed, which form a self-healing solid lubricant layer on surfaces at points of contact. Because water is a product of combustion, oils contain emulsifiers to prevent water films from rusting or corroding parts. To help make oil flow in winter cold-starting, pour-point depressants surround waxy components of the oil before they can clump together. Lubricity agents—long-chain molecules terminating in functional groups—adhere to metal surfaces at all times, reducing the friction between them. If you disassemble a modern motorcycle engine, you will find that its oil system is very comprehensive. Here we have a camshaft, whose rotating lobes press against the valve tappets to open and close the engine’s valves. It is normal for oil under pressure from the engine’s oil pump to be supplied to the hollow interior of the shafts, emerging through drilled holes to lubricate every camshaft bearing, and every cam lobe and tappet. Thanks to 130 years of engineering, it all works very nicely. (Jeff Allen /)Oil-additive chemistry is a work in progress, as conditions in today’s smaller, harder-working but more fuel-economical engines become ever more severe. Modern premium petroleum oils consist of hydrocarbon molecules that have been reshaped to give them desirable structures. Synthetic oils are made by linking together hydrocarbon elements such as ethylene gas to form desirable oil structures. Makers of reformed- petroleum oils and of synthetics are working toward a common ideal. Consult your owner’s manual to find out which oil-viscosity grade—such as 5W-30—and service category—SN, etc.—have been found to perform best in your engine. This information is printed on the oil container itself. In a few cases, synthetic oil only is specified by a manufacturer. Source

Released in 1972, the Aluminum XR750 won the Grand National Championship in its first year. This is a 1975 XR750 shown above. (Harley-Davidson /)A crucial difference motorcycle sport has long lorded over its four-wheeled counterpart—and continues to even in today’s electronics age—is the simple fact that the human behind the controls on a motorcycle remains the ultimate factor determining wins and losses. For all the decades of developmental work and mechanical black magic behind it, there’s no denying that the historic success of Harley-Davidson’s XR750 is intrinsically tied to the heroics of a select group of otherworldly riders. As covered in the previous installment, when presented with rule book hurdles in the late ’60s, H-D responded with the creation of the original Iron XR750 in 1970 and then further iterated on that design with the superior Aluminum XR750, released just two years later. The result of that engineering exercise was a well-balanced, rider-friendly package that provided a wide range of flat track artists an outstanding brush with which to paint their masterpieces on oval canvases of dirt and clay. Two legends of the sport, Parker and Springsteen rode side-by-side for Harley-Davidson beginning in 1981. (Mitch Friedman/)The ’72 machine was so good, in fact, it won the Grand National Championship in its first go and positioned itself as an unbeatable machine going forward. However, as formidable as the XR and its rider lineup may have been, Harley-Davidson was beaten to the throne in ’73 and ’74, despite the fact that a full 10 different riders claimed at least one victory on the XR750 through the end of that season—each one an eventual AMA Motorcycle Hall of Famer, save Dave Sehl, who was inducted into the Canadian Motorcycle Hall of Fame. But even with all of those future hall of famers in its corner, H-D and the XR750 were ultimately outdone and outclassed by a truly transcendent talent in Kenny Roberts, despite the Californian being significantly outgunned on his Yamaha XS750. To overcome Roberts, Harley needed its own “King.” It might have already had one in Gary Scott, who actually beat Roberts for Rookie of the Year honors in ’72 and then finished as runner-up to him in ’73. Scott decked out in the unmistakable Harley-Davidson uniform in 1975. (NASCAR Archives/)Harley-Davidson signed Scott to the factory team in ’74. And after notching up a second straight second-place season, he finally delivered Harley another Grand National Championship in ’75—before promptly leaving the squad in a contract dispute following the season. Desperate to replace Scott with a new rider—one who could go head to head with Roberts and Scott and somehow come out on top—Harley-Davidson turned to a flashy 18-year-old named Jay Springsteen, who had just earned Rookie of the Year honors. Bill Werner, who was fresh off earning his first GNC title as a mechanic, knew things were going to be quite different within minutes of the first official meeting with “Springer” ahead of the ’76 season. The first rider to achieve 30 wins in Grand National competition, Springsteen made waves early on in his career. (AMA Archives/)“(Team manager Dick) O’Brien said, ‘Hey we're going to have Springsteen come over to set up the bike for the Houston TT.’ Springer came into the shop and said, ‘Where’s the bike?’ I asked him if he wanted the rear brake on the right or the left. “And he said, ‘If you put it on the left, I’ll step on it over there, and if you put it on the right, I’ll step on it over there.' “‘What about the handlebars? “ ‘Wherever they are is where I’ll put my hands.’ “And within two minutes he got on it and said, ‘Yeah, that’ll be okay.’ “Gary Scott was very, very finicky. I was used to working with a guy who had me taking a quarter inch of foam out of the seat because he didn’t feel comfortable on it. I went into O’Brien’s office and told him we were done setting up the bike, and he said, ‘What do you mean you’re done?’ “I told O’Brien, ‘He said he’ll ride it just the way it is, and that's fine.’ ” It was “fine” by even the most outlandish boundaries of the definition. Springsteen defeated Roberts and Scott to claim the title in ’76 and then again in ’77. And for good measure, he added a third straight Grand National Championship to his résumé in 1978. Springsteen established himself as the winningest rider in series’ history relatively early in his career, and continued to build on that tally all the way into the new millennium. To this day, his 43 victories have only been eclipsed by three riders. Werner said, “Jay was just a huge natural talent. He didn’t jog or lift weights. He didn’t do any of that stuff. He rode motorcycles in the woods and did normal stuff, but he didn’t have a specific diet or a trainer. And he was always amazed that other people couldn’t do what he did. “He said, ‘Come on, this isn't that hard.’ And I was like, ‘You’re only an inch away from the fence all the time, doesn’t that scare you?’ ‘Nah. As long as you don’t hit the fence, you’re okay.’ "Springer" launches his XR750 over a TT jump. (AMA Archives/)“I remember at Toledo, Kenny Roberts had set the fast time in time trials, and then Jay went out and went faster. When Jay was coming into the pits, Kenny sat there watching and said, ‘Springer, I’m kind of curious. What’s your shut-off point going into Three? What’s your mark?' “Jay said, ‘Shut-off point? I just hold it wide open and try not to crash.' “Roberts walked away and said, ‘This guy is nuts…’ “He just ran it in there until the front end pushed and then the rear end came around and he saved it and stayed on the gas. There was no plan, just stay on the gas. “Jay did refine his skills over time, and he got a little more artful and realized that not every track was just a wide-open thing. He got better on grooves and whatnot, but in his early years his mentality was that the fastest way around was holding it wide open and trying not to crash.” Guts clearly weren’t an issue for Springsteen, which makes it a sad irony that his stomach actually was his Achilles’ heel. Over the next few seasons, Springer missed numerous main events due to a mysterious ailment that doctors attributed to excessive acid flow brought about by nerves. Just one season after winning Rookie of the Year, Springsteen earns his first Grand National Championship in 1976. (NASCAR Archives/)That opened the door for others to rush in, and the next five Grand National Championships went to four other riders armed with XR750s. Each one of them a future hall of famer and with no overlap to the 10 already referenced. Despite the XR750’s continued success, Harley-Davidson again found itself searching for a handpicked successor who could rack up victories and string together multiple GNCs the way Springsteen had in the late ’70s. And again, it turned to a young rider bursting with talent in ’79 Rookie of the Year Scott Parker, drafting him up to the works H-D squad midway through the ’81 season. However, the early and mid-’80s were a tumultuous time for Harley-Davidson in general, putting the factory race effort in dire jeopardy. It was extremely bad timing, as Honda was preparing to introduce a game changer. Later becoming the winningest rider in the history of the sport, Parker's swagger and style are unmistakable on the racetrack. (Dave Hoenig/)Honda followed Yamaha’s playbook to beat Harley-Davidson by hiring a pair of ascending superstars in ’82 GNC champ Ricky Graham and the ultra-talented Bubba Shobert, and then took it a full step further by following Harley’s own playbook on the machinery side of the equation. After enjoying only limited success with its CX500-based NS750 flat track machine in 1981 and 1982, Honda closely studied the basic designs of the XR750 and then added them to a prototype V-twin engine that had originally been slated for a rally bike. Like the XR750, Honda’s new RS750 featured a four-speed 45-degree V-twin (right down to identical 79.5mm x 75.5mm bore and stroke numbers) but it also had four valves per cylinder and overhead cams as opposed to two valves and a pushrod design. The engine that replaced the NS750, and catapulted Honda to the front of the Grand National Championship pack. (Drew Ruiz/)“Honda was smart,” Werner said. “They bought a couple XRs, and they took them apart because the XRs worked so well. They duplicated the flywheel mass and the V-twin configuration, but they were pretty sure they didn’t want pushrods or two valves. So essentially, it had a lot of the plus characteristics of the XR with none of the minuses. “It didn’t really make any more power than an XR, it just made more rpm. So what’s the advantage? If an XR comes off the corner at six grand and the Honda comes off at seven grand and the terminal velocity is the same, they start up a thousand rpm on the band and just have more power on tap due to the rpm difference.” The RS750 was tested in action during the ’83 season (and even won the Du Quoin Mile courtesy of Hank Scott) before being fully unleashed on the series in 1984 with Graham and Shobert at the controls. It proceeded to capture four successive Grand National Championships: Graham in ’84 and Shobert in ’85, ’86, and ’87. Honda’s RS750 collected four Grand National Championships in as many years with Ricky Graham and Bubba Shobert. An AMA addition of restrictor plates was instituted in 1987—a highly controversial measure that is still argued with vigor to this day. (Drew Ruiz/)Meanwhile, Harley’s full factory effort had been effectively mothballed with the race department reduced to just a single employee—Bill Werner—whose job at that point primarily consisted of shipping out parts to privateer teams. However, even if the factory H-D team no longer existed, Parker insisted on having factory-level talent building and wrenching his XR750. Werner said, “In ’85, the factory disbanded its racing team and gave all their riders their equipment and told them to hire their own tuners and stuff like that. About one or two races into the season, Scott Parker called and said, ‘I’m not happy with the guy I hired. I want to hire you.’ And I told him I was working full time and couldn’t do that. And he said, ‘Well, I'd rather have you working on my bike four hours a day than the other guy for 20.’ “I agreed to go to work for him, but Harley-Davidson management didn’t want it to happen. They told Scott, ‘Nope, your contract says we get to authorize anybody you hire to make sure they’re competent.’ “Scott took it to his attorney, and his attorney said to Harley, ‘You’re right. You have the authority to judge whether the guy is competent. And this guy has won four national championships. How can you say he’s not competent?’ Parker and Carr leading a pack of talented riders at a Mile later in Parker’s career. (Dave Hoenig/)“Harley tried to argue that I wouldn’t have the time to do the job correctly, but Scott’s attorney said, ‘That’s not what the contract says. The contract only says competent.’ “So reluctantly, they let me go to work for Scott, and I did it all at home.” Parker enjoyed his finest campaign as a professional yet that season, including a massive win at the Indy Mile which finally halted Honda’s dominant streak of mile victories that had stretched into the double digits. He ended the season ranked third in points and followed that up with a runner-up showing the following year as he and Werner continued to seek out new ways to derail the Honda freight train. Werner said, “The RS was just a better engine than what the XR was. But it had its quirks too. It hit so hard it burned up tires more than what the XR did.” Restrictor plates were added to the equation in 1987. Most will tell you the move was done solely to undercut the inherent advantages of the RS750 as a favor to Harley-Davidson, but Werner argued it was the Honda’s one weakness, in part, that brought a penalty upon itself. “(Burning up tires) was one of the reasons the AMA instituted the restrictors. They wanted to slow everybody down. There were a couple races in particular where the top riders went right through their tires. Goodyear wasn’t about to make new tires for that small a market. They transitioned to Carlisle tires for a while that were harder, but they’d go through those tires too. They had to keep shortening races from 25 laps to 20 laps to 15 laps and pretty soon the competition committee said, ‘This is nuts. Why don’t we just slow everybody up? You don’t have to go 130 on the straights. Why not just 120?’ It hurt all engines about the same. Having them all close was the key.” Parker came within seven points of dethroning Shobert in 1987. If anything, the XR750 platform had been made stronger due to the lessons learned during the race program’s hiatus and Honda’s run of dominance. And just as Harley-Davidson amped its factory program back up to full bore, Honda was gearing down and looking to exit, frustrated with the new regulations (in racing and in the marketplace) that had been put into place. Werner explained, “Before I brought the program back into Harley-Davidson, I worked with different vendors and developed different cam profiles and other things that made Scott’s bike, I think, better than everybody else’s. “We had an advantage, and it wasn’t due to the factory giving me s—t because they only reluctantly allowed me to do it at all. But rather, I had the freedom to go to any vendor I wanted because I was on my own working out of my own garage. And a lot of those things got transitioned to the official product when I ultimately got to work in the department full time and they hired back more staff and a manager and all that other stuff.” Parker did finally overcome Shobert to end Honda’s championship stranglehold in 1988 while starting one of his own; he would go on to claim four consecutive Grand National Championships from ’88–’91. Ultimately, the challenge to Parker’s crown would come from within the team. Parker collecting the hardware for one of his many victories. Parker currently holds the record for most career wins at 94. (NASCAR Archives/)Harley-Davidson had learned to have a worthy heir in place. Just one year after Parker’s reign began, it found one in the gifted 1985 Rookie of the Year Chris Carr. Carr’s skill set was a bit different than Parker’s, which worked well in terms of making the factory XRs heavy favorites virtually every weekend, no matter the discipline, year after year. Parker was the unquestioned maestro of the mile; he raced the XR750 to an astonishing 55 mile victories during the course of his career (more than twice as many as the current master of the form, Bryan Smith). Carr, meanwhile, was an unstoppable force at the TTs and the short tracks. And both riders were among the greatest half-milers the sport has ever seen. Both styles worked equally well at racking up championship points. The next decade saw Parker and Carr engage in some of the greatest title fights in American Flat Track history. Parker’s ’91 title win over Carr came down to a tiebreaker, and then Carr struck back with his first Grand National Championship the following season, ending Parker’s run of four straight GNCs by just two points. Ricky Graham broke up the epic annual intra-team title fights with an amazing ’93 season to give the RS750 one final run to glory, before Parker reclaimed the number 1 plate in ’94, this time by four points over Carr. Carr was drafted into the factory Harley-Davidson AMA Superbike team in ’95 and would focus the bulk of his efforts hustling the VR1000 around on pavement for the following three years. During that time, Parker continued to stack up titles, the last (his ninth) coming by a scant two-point margin over Carr in ’98 upon his rival’s full-time return to dirt track racing. By ’99, Carr was running his own team, had Kenny Tolbert wrenching his XRs, and had rounded into an all-around dirt track master—miles very much included. He scored a blowout title triumph in Parker’s farewell season, setting the stage for a run of six dominant GNCs from ’99–’05. That string was broken up only by Joe Kopp’s 2000 Grand National Championship, earned while Carr was splitting his time winning the short-lived Formula USA National Dirt Track Championship. Parker (left) versus Carr (right) was a clash of titans on dirt. (Dave Hoenig/)Reflecting on the Parker-Carr years, Kopp said, “It was pretty wild. They had some really heated years right before I stepped in. I got in late in their battle, and then Chris and I got to have a lot of battles ourselves over the years. It was really neat to be a part of that. Any time that I got to race Scottie or Ricky or Chris… Gosh, it was a helluva race. “I remember Scottie’s last Springfield in 2000. Even though I was credited as the winner at the Dallas Mile in ’99, that race was red-flagged and ended on lap nine. So in my mind, I didn’t have an official mile win at that point and was still looking for my first. Will (Davis) got his first mile win that Saturday there at Springfield, and I finished second. The next day, sure as s—t, Scottie Parker is here—‘Mr Springfield’—and he comes out of retirement and goes and wins the thing and I got second again. I was like, ‘Damn!’ Even though he had been retired for a year or whatever, it was just an honor to race with him in a situation like that. “I wish I could have been in the middle of more Scottie and Chris battles,” Kopp said, “but I had my fair share. I got frustrated enough in the few that I was in.” One of the most versatile riders in the history of flat track, Carr showed a unique finesse on the motorcycle. (Dave Hoenig/)Carr continued to race into the 2010s, setting the bar extremely high during what was the formative era for a number of the today’s crop of AFT SuperTwins aces. Ultimately, the three titans of the XR750—Jay Springsteen, Scott Parker, and Chris Carr—combined to score a nearly unthinkable 183 GNC main event victories and 19 Grand National Championships on the iconic machine. Next time: Can the XR750 still win today? Source

Will we see the fruits of Kawasaki’s electric bike project anytime soon? (Kawasaki/)Electric motorcycles have been making headlines for years now, but despite the publicity it’s still almost impossible to actually buy a convincing battery-powered motorcycle from a major manufacturer. The Harley-Davidson LiveWire and BMW’s C-Evolution give early adopters a route to electric power, while small firms like Zero lead the way with their all-electric ranges, but we’ve yet to reach the point where two-wheeled EVs are a mainstream alternative to gas-powered machines. Despite the current lack of production options, a development battle is raging behind the scenes as major bike manufacturers work to ensure they aren’t left behind in electric bike technology. Back in November, Kawasaki quietly wheeled its electric bike project into the public eye, putting a prototype sports EV on its stand at the EICMA show in Milan. Since then the firm has trickled out videos of the machine in action, but don’t be fooled into thinking it’s a new project; this work has been going on for a decade. Kawasaki wheeled out an EV “project” prototype at last year’s EICMA show but made it clear it would not be a production model. (Kawasaki/)Kawasaki’s own figures for its electric bike are a hint at its age. As with most electric bikes, it has two power figures—one set being the absolute peak that can be achieved for brief periods, the other a “continuous” maximum that can be sustained indefinitely without overheating the motor. Disappointingly, the absolute maximum for Kawasaki’s EV is pegged at 20kW (around 27 hp), while the continuous figure is 10kW (13.5 hp). In a world where you can walk into a Zero dealer and buy an electric SR/F or SR/S making a peak of 110 hp right now, those numbers seem a bit underwhelming for a prototype from a tech giant like Kawasaki. Stated numbers for Kawasaki’s EV are far from impressive, which hints at the project’s longevity and prototype status. (Kawasaki/)It’s not like the Kawasaki is a much smaller, lighter bike either. The firm says it weighs in at 483 pounds (just 2 pounds less than a Zero SR/F), and its range of 60 miles is around half as far as the Zero can manage on a charge. With numbers like those, it’s understandable that Kawasaki is at pains to point out this isn’t a machine that’s going into production; it simply wouldn’t stand a chance against the limited competition that’s already out there. Patents from years back show older Ninja 300 bodywork, wheels, and other components, and Kawasaki itself has said there are no plans for a production EV in the near term. ( Japanese Patent Office/)So what’s the point then? The disappointing numbers that Kawasaki gives its electric prototype fall into perspective when it becomes clear how old this project is. Kawasaki’s first patents showing a bike similar to this were filed back in 2010 and detailed designs showing this very machine appeared in patents just a couple of years later. Carry-over components including the bodywork, wheels, brakes, and suspension are from the 2013-spec Ninja 300, further confirming its age. Perhaps if you consider it as an electric bike from 2013 rather than 2020, the figures for range, weight, and power aren’t as comprehensively outclassed as they seem now. Multiple sources at Kawasaki including Yuji Horiuchi, president of Kawasaki Heavy Industries Motorcycle & Engine Company, have clearly stated that this bike isn’t for production. In fact, he went further, saying there are “no plans” for a production EV in the near future. Older patent filings show battery and electronics removal from the EV project bike. The evolving technology is becoming more and more cost effective, and Kawasaki is likely waiting for the right time to roll it out. ( Japanese Patent Office/)The reason for that is one of simple economics; at the moment it’s virtually impossible for a large motorcycle manufacturer to mass-produce an electric bike that will sell at a reasonable price and turn a profit. You either need to go niche and hope that a small number of buyers will be prepared to spend a lot to be early adopters—think Harley LiveWire—or target the low-cost, low-tech Chinese market for battery-powered scooters. But the economics are constantly changing. Batteries and motors are getting better and cheaper while ICE-powered bikes are getting costlier as they’re forced to meet ever-stricter emissions limits. By keeping a group of engineers working on electric bike technology and testing designs and ideas, it means that when the price-to-performance ratio shifts enough to tip the balance of profitability to a point where it favors electric bikes, Kawasaki should be ready to go without having to start from scratch. | 5.Kaw-EV-Racing.jpg | What’s interesting about Kawasaki’s project is that it contains a four-speed gearbox unlike the typical single speed found in most current electrics. A manual transmission allows a greater speed range and also allows the rider to have more input. (Kawasaki/)Notably, Kawasaki’s solution includes a purpose-made four-speed gearbox between the electric motor and the front sprocket, giving an additional layer of control compared to the usual single-speed design that most electric bikes use. It’s there for rider engagement as much as any performance gain, making a bike that’s more appealing to riders raised on a diet of gasoline. The firm’s European PR boss, Martin Lambert, said: “This is a vehicle which is really just testing the technology. It’s not going to go into production but it just shows that Kawasaki is looking at electric vehicles. “Most electric bikes don’t have gearboxes, so you just turn them on, twist, and go, rather like a scooter, whereas this bike has got four gears. So you’ve got the electric power pack and the motor is connected to the gearbox. Firstly it will appeal to motorcyclists, because they want to still change gears. So that’s a good advantage and a crossover between gasoline engines and electric engines. Electric vehicles are definitely in Kawasaki’s future, we just don’t know how far out. (Kawasaki/)“The interesting thing about the testing was that it wasn’t just for durability and reliability, they were testing it for fun. They wanted to know whether the riders had a fun experience.” Check out the technology in this video. Source

This selection of jets is for two Mikuni VM carburetors. The pair in the center showing the tall one standing up and one like it laid down next to it are the needle jets. The tapered carburetor needle works with the needle jet orifice to meter fuel on between roughly 1/4 and 3/4 of throttle lift. (Mark Hoyer/)As proof there is always something more to discuss in carburetor tuning, reader Jim Mosher commented that I left out of my “How to Tune Carburetors” story any discussion of the needle jet size as an element in carb tuning, and he is quite right. Back in 1971 when I was race tuning two-strokes, I learned something about needle jet effects from accomplished tuner and parts-maker Harry Hunt. He started the conversation by noting that there is some variation in the dimensions of carb tuning parts, such that it can be well worthwhile to try some variation, plus and minus, just to be sure where we are. Without coming right out and saying “Do this” he implied that needle jets were an underused resource. English rider Cliff Carr on an Arlington Motorsports Kawasaki KR500 tuned by Kevin Cameron in the early 1970s. (Cycle World/)Early the next season my rider Cliff Carr and I trucked our 250 up to Loudon, New Hampshire, for a tuning day. I brought along a range of needle jets to explore the point Hunt had made. Carr went out and did a few laps for baseline, and we began trying needle jets other than what came in the bike. He’d do five timed laps, come in, and we’d discuss how the bike had performed. Just when it seemed that we might as well have been trying various stiffnesses of seat padding, here came a group of five laps that were four-tenths of a second faster on average than previous. As Carr rolled in the pit road I made an effort to smooth out my face and look bored. “How was that?” I asked in a neutral voice. “Seemed kinda…flat,” was his reply. “Okay, how about this?” I said, giving him the stopwatch board. His eyebrows went up. Four-tenths seems pretty insignificant by itself, but do that for 15 laps and it adds up to reaching the finish line six seconds sooner. This selection of jet needles shows the first 20mm or so of the needle (on the clip end) is straight, and only as the throttle is turned does the taper start to act in the fixed orifice of the needle jet. As the needle tapers sharper, more area of the jet is exposed and therefore more fuel flows. (Mark Hoyer/)Mr. Mosher notes that the first 20mm of the jet needle are not tapered at all; they are cylindrical. So changing the diameter of the needle jet gives control over mixture during initial slide lift—control that is independent of the control given by varying throttle slide cutaway. When Cliff described the engine as “kinda flat” it may have been just that. If a carburetion change smooths out power delivery, it becomes comfortable to use more of it, and the laps become faster. On the accompanying graph, I have put throttle slide lift in millimeters (mm) on the y (vertical) axis, and fuel delivery orifice area (area of needle jet minus area of needle at that slide lift) on the x (horizontal) axis. Throttle slide lift is shown in millimeters (mm) on the vertical axis and fuel delivery orifice area is shown on the horizontal axis. The effect of moving the needle up or down is shown by the different lines through the middle of the graph. (Kevin Cameron /)Note that there is no change in fuel orifice area during initial slide lift. That is because it is the cylindrical part of the needle that is in the needle jet. After that, it is the taper of the needle that is in the needle jet, so the fuel orifice area begins to increase on a slope, upward and to the right. Raising or lowering of the needle just raises and lowers the sloping line, making fueling richer or leaner “on the needle,” which is from roughly 1/4 to 3/4 of throttle slide lift. Source

Patent drawings show Honda looking at a larger replacement for its NC750 model. (Japanese Patent Office/)Take a quick look at Honda’s latest patent application—recently published via the Japanese patent office—and you’d be forgiven for thinking it shows the existing NC750S or even the original NC700 model. But look closer and it actually reveals a completely new engine that might well form the basis of the firm’s next-generation NC range. Honda is widely expected to reveal a revamped replacement for the NC750 models later this year. Believable rumors from Japan suggest the firm will increase its capacity once again—the original NC700 was 690cc, the current NC750 is 745cc, and the next model is likely to be in the region of 800–850cc to retain performance while reducing emissions. However, if this patent is to be believed, the changes will be much greater than a simple bore and stroke increase. The new engine design (black) in the patent is more horizontally oriented than the existing NC750 mill (red), and is also more compact. (.Japanese Patent Office/)Unicam Cylinder Head Overlay the outline of the engine shown in the new patent and the existing NC750 motor and it’s instantly clear the two designs share little, apart from their general layout. The new design appears to be intended to lie flatter than the current one, with the cylinders running almost parallel with the ground. That change would increase the already substantial storage space above the engine in the NC range of bikes but, given an increased displacement, could also pose a packaging problem, with the cylinder head invading the space needed for the radiator—or even interfering with the front wheel when the fork compresses. Honda’s solution is to make the cylinder head more compact, and the patent illustrations show the new engine featuring the Unicam layout that first appeared on the CRF450R back in 2002. Instead of the camshaft being under the rocker arms, the Unicam design (seen here on the CRF450R) places it above the intake valves. (Honda /)While the existing NC750 engine is already a single overhead cam design using rockers to operate four valves per cylinder, the Unicam achieves the same goal but takes up less space. Instead of having the camshaft underneath the rocker arms in the center of the cylinder head, it puts it directly above the intake valves. That means it operates directly on the intake valves, rather like a DOHC camshaft would, while additional exhaust lobes act on triangular rockers to operate the exhaust valves. RELATED: Honda’s 2018 NC750X Is Every Scientist’s Favorite Bike The result is a cylinder head that’s shorter overall than a typical SOHC design, and one that’s particularly compact on the exhaust side of the head. What’s more, it allows for a tighter included valve angle, making the head narrower and allowing for a flatter combustion chamber for a higher compression ratio. Unicam has already been used to great effect on the CRF450R, which demonstrates its DOHC-style performance potential, and on the VFR1200. It’s also a feature of the latest Africa Twin. The Unicam layout is also in use on the VFR1200. It takes up less space and is more compact on the exhaust side of the head than the existing NC750 engine. (Honda /)More Compact Transmission Like the current NC750, a key feature of the new design is Honda’s dual-clutch DCT transmission, which allows for seamless up- and downshifts at the touch of a button or even automatically, without a momentary loss of drive. This gearbox works just like the firm’s other DCT designs; the input shaft is split into two halves, one carrying first, third, and fifth gears, and the other bearing second, fourth, and sixth. With a clutch for each half of the input shaft, two gears are selected at any one time, but only one clutch is engaged. Changing gear is thus simply a case of disengaging the first clutch and engaging the second. While none of this is new, the aspect that Honda’s latest document appears to be trying to patent is a built-in hydraulic actuator for the gearbox, replacing the usual separate actuator. Unlike the existing NC750 DCT, which has its actuator unit bolted to the side of the gearbox, the new design features one that’s integrated into the top of the transmission, making it more compact overall. Any replacement for the NC range will need to be adaptable to a host of different applications, from scooter to adventure bike. (Japanese Patent Office/)Key To A Host Of New Models The original NC700—launched in 2012—and the updated NC750 that followed two years later have become the building blocks of a surprisingly wide array of bikes. Along with the NC750S naked streetbike and NC750X adventure model, the Integra scooter is based on the same engine and chassis. Honda’s CTX700 and CTX700N cruisers are also spin-offs using many of the same components including much of the same engine and frame design. Wilder variations on the theme have included the sci-fi-styled NM4 Vultus and hard-to-classify X-ADV, which sits all alone as the world’s only adventure-inspired 750cc scooter. Any replacement for the NC750 therefore has a lot of roles to fill, as the same engine and chassis is likely to be used in successors to all those machines. Sign up here to receive our newsletters. Get the latest in motorcycle reviews, tests, and industry news, subscribe here for our YouTube channel. Speaking of the chassis, although Honda’s patent shows the new engine in the old NC’s tubular steel frame, it’s clearly not designed to fit there. The engine mounts don’t line up and the new engine is obviously intended to be mounted more horizontally. That means when we do get to see the bike this engine is really designed for, it will feature a completely different frame design. The engine’s suggested 850cc capacity combined with its parallel-twin layout and the Unicam cylinder head also mean it could be related to the “baby” Africa Twin model that’s the subject of a growing number of rumors. While a smaller AT makes sense, particularly given the existence of rivals like Yamaha’s Ténéré 700, BMW’s F 850 GS, and KTM’s 790 Adventure, Honda doesn’t currently have a suitable engine to power it. Could a bigger, more rugged NC850X be better positioned to compete against the Ténéré and BMW F 850 GS? (American Honda/)One solution could be to give the replacement for the NC750X, one of the bikes this engine is likely to be destined for, a more rugged appearance and greater off-road ability with wire wheels and longer-travel suspension. Source