I've finally come around to getting the BSA back together and I've made a note of something the experts may clarify. I am no stranger to motorcycle engines. Most of what I've been around has been more modern though. I always remember reading about ring material being reliant on what the material in the cylinder was of.
I just compared the old rings to the new ones I ordered (hepolite). It appears that the old rings are the same material as the cylinder liner. I was always told that this would prevent the rings from bedding in properly. The new (hepolite) rings are of a different material and seem to be much softer. Maybe this is the problem I was having all along. Is it possible that the old rings I removed were designed for use in a cast liner without a sleeve? And the hepolites are designed for a pressed in steel liner?
Hi Michael...Following a problem with premature cylinder wear, for a short period BSA used hardened cylinder liners..pre war and just into the war I think. It may be that your original ring set was for one of those...Ian