If it's the same family I met they're from Wolverhampton, I think the guys name is Eddie ? He's got a Kawasaki VN1500, I sent him a workshop manual after our visit.
My mate had the DT250 , it wasn't as good as the 175. I had a XT500 enduro , it was a heavy lump, great engine but not great 6v electrics . Worth crazy money now .
If they'd have been Polish it would have been off the van and fitted in less than 10 minutes (Fat munters excepted) but of course they're not allowed to work here now are they ................