When you said you wanted to get some air on one like Gunter I thought you meant Anthony
so glad I logged in while reading this thread otherwise I wouldn't have seen the picture.
Urals, otherwise known as Cossacks.
My older brother bought one secondhand back in the early seventies. Dad told him how great it would be as he had this thing about horizontaly opposed engines & shaft drives being the best. And this was afterall a copy of the early BMW, how bad could it be?
Well, the Chinese weren't the first to invent bad copies.
Dad was impressed at first, so much so that he went out & bought a new one. He had been without a bike for fifteen years or more.
Then they started having troubles allthough I can't remember exactly what, wasn't really interested in them myself that much as they weren't dirt bikes.
I do remember though that my brothers one broke a crankshaft. The plate that holds the bigend to the main broke & I think it was bolted in. Dad searched the yard for a peice of 3/4" plate & cut out a new piece, machined it up in the lathe, trimmed the sides off & bolted it back together. He set up 2 pieces of flat steel on edge on the sawbench & set them with the spirit level, sat the crank mains on the straightedges & watched for where it rolled to & then drilled a small hole in the lowest part of the crank half ( lowest being heaviest) until he thought it was balanced enough to reassemble.
It ran fine but after a couple of months my brother traded it on a new Yamaha. Not long after my Dad traded his for a Gold Wing.