It still ran?? Wow
Oh they run. Sometimes it is amazing how. This year my 1930 BSA Sloper just had a complete brake down - it just died in the middle of a tour and wouldn’t start anymore. When I measured compression later the gauge showed 0! I thought the gauge was broken.
When I opened the engine I found what you see in the pics. The rings had soldered themselves in the grooves too. The cause was lack of oil. The BSA sloper has manual oil flow regulator, just like a small tap one can open up more or less according to your needs. There isn’t a glass or anything where one can actually see how much is flowing. Idiot me just kept shutting it down to avoid her smoking like a steam engine - didn’t want to bother the neighbours and all that... I don’t know how many miles she ran like that, but a lot anyway, at least a whole season of rides and going to meets. Never did she really complain or showed any signs of heating up or something, the good old girl. She accelerated well and had power - the only thing was she never reached top speed, but who rides a 90 year old motorcycle above 100km/h anyway?
Now I’m waiting for a bore from the machinist and then will have a new piston made like Klaus here.