Join Date: Nov 2009
Location: Lander, Wyoming
I will suggest that the cylinder, piston, rings & valve stems were Not fogged with storage oil thru the carburetor intake when the bike was stored, how long ago?
Therefore there was/is probably some light surface rusting of the cylinder & rings. This may polish off with more run time. Did you squirt or spray any oil into combustion chamber, prior to rotating the engine over, during cosmetic restoration?
Nowadays, people with smart phones can purchase borescopes/cameras on a wire to insert thru small holes and have a look inside.
The construction of the valve train mostly reduces the possibility of oil passing between valve stems & guides. But if the cylinder was removed for piston & ring replacement one would want to refurbish the valve & seat faces and replace the valve seals also.
Is there any chance that the engine oil is contaminated with fuel?
Modify at "YOUR OWN RISK"!
Still riding my 1987 KL650-A1. 83,000+ miles & counting