Motorcycle Repair: honda cb650c-smoking, valve seals, combustion chamber

Question
not sure if you can help but we bought a 25 y o cb650 restricted to 250cc. it was noted to be a smoker once warmed up. we bought a used piston/barrel/rings, changed oil/filter, spark plugs etc etc but it still smokes. any ideas?

Answer
I dont really know much about hondas, but if you are getting smoke when the bike is running, its either oil getting past the rings or the valve seals are leaking and letting oil into the combustion chamber.
When you replaced the rings did you hone it. If you dont you will get smoking
Good luck and happy riding
mike