hello i have a 96 yamaha timberwolf that smokes slightly. when i first bought it, it did'nt smoke but then i changed the oil and now it smokes slighty. i used valvoline atv oil 10w-40. the smoke is not black but a sort of bluish and only smokes periodically usually at startup and very little. my question is, could this be that i need to do a ring job? or something to do with the oil change. someone told me it could also be carb problems or a dirty air filter. what does different color smoke mean? thanks

 

My wife's 04 Bruin smoked on start-up when we first bought it(used) and I changed to oil to Amsoil atv oil, 0w-40 and the smoking stopped. As God is my witness...it stopped.
Now buying Amsoil may not be an option for you, Shell Rotella synthetic may be as that is what I use now in her Bruin. And it still doesn't smoke on start-up.

Blue smoke on startup that dissapears is a sign of worn valve stem seals. Oil that's in the head arear, leaks down through the seals and collects in the combustion chamber where it's burned off after the engine is started. Blue smoke coming from the exhaust all the time is a good sign the rings are worn.

Black smoke is a sign of the engine running in a rich condition.