smoking 350x???

[Super350]

would a 350x smoke for any other reason besides piston/rings/cylinder being worn? Mine smokes like a $%#$@!. Could valves being out of adj. make it smoke? thanks

[matt22895]

Valve seals could be worn but the smoke usually either goes away when warmed up or is worst when high rpms or deceleration occurs.

[yamaha driver]

yea agreed matt. rings would make it smoke all the time with the same amount of smoke. and it would smoke more when under load or getting on the throttle

[atc007]

A engine can only smoke like that for one reason. Burning oil,and quite a bit of it. Oil can only get into the combustion chamber 3 ways. 1 .Something is cracked /broken,,like a head,,wild port job that cracked. Highly unlikely. 2. valve seals,,the seal drys out and allows oil to SEEP down the valve stem into the port,introducing itself into the combustion chamber. Also,unlikely. 3. And almost ALWAYS the cause,rings not seating to the cylinder. Usually caused by low oil/ high heat at one point. You almost certainly will need a bore job,fresh piston and rings and a valve job. then you'll be fresh as new. If your air filter has been dirty/and or unoiled over the years. Your intake valves will be worn. And 350X's tend to be a little hard on exhaust valves,,especially the left one for some reason. You can pull off your breather tube while it's running to verify smoke there. That will tell you the problems in the cylinder.

[bmanley]

Had the same issue with mine and it was pretty much the same as metioned above. Cylinder needed bored due to excessive heat, rings were shot, one cracked valve guide, and needed all 4 valves. It wasn't cheap, but it should be good to go now. Just got everything back from the machine shop and getting ready to put it back togather.

[jb2wheels]

My 85 smokes like a hippie. The ring-dingers complain when they follow me instead of the other way around.

It had no air filter on it when I got it. Well, it had a hole in the crankcase, too. I'm sure they're contributing factors.

On the other hand, I plan to keep the oil topped up and ride the crap out of it. If I get to ride it 6 times a year I'm doing good. Hard to justify the $$ for a top end but I might do it.

[Super350]

well an update if anyone cares....replaced the rings even though they werent bad and piston was fine, laped and replaced all the valve seals and the 2 exhaust ones were hard as a rock so looks like that was the main issue. havent got it back in the frame yet but but everything should check out. Thanks for all the info guys