GZ250 Smokes on cold start, stops smoking after running
 

My bike spews blue/white smoke every time i start it after letting it sit a while. After a few minutes, the smoking stops and it purrs like a kitten. I've done some research on the issue, and it looks like it might be a sticking valve or worn valve seals causing oil to drain into the cylinder after i kill the engine. Then upon start up the oil that drained into the cylinder burns off in a cloud of ninja smoke. I ordered some new valve seals and plan on replacing them later this week. I'm also going to soak the entire cylinder head, inner block, etc., in Seafoam to get rid of any excess carbon. If this doesn't fix it, I'll move on to checking the cylinder walls and piston fit, etc. (engine has good compression already). If anybody has any suggestions, send em my way. I plan on posting the results once all is said and done.

Re: GZ250 Smokes on cold start, stops smoking after running
 

If you've got good compression, I don't think that piston fit would be the problem. :)

Re: GZ250 Smokes on cold start, stops smoking after running
 

How many miles are on your engine ? Sounds like a bad valve seals.

Re: GZ250 Smokes on cold start, stops smoking after running
 

How often and how much oil do you need to top it up ??

Re: GZ250 Smokes on cold start, stops smoking after running
 

Still waiting on the valve seals to arrive. Yeah I read some "mechanic" on an alternate forum say that if your engine is smoking, you have bad piston rings and should immediately replace them to avoid catastrophe. This sounded more like chicken little than sage advice, and I figured I'd put my case up for posterity. My impression is that it is the valve seals (and I get the impression that you guys agree) because the bike runs great and has good compression. Also I would fix them first anyways because it's a $10 fix.

The bike barely consumes any observable oil. I can't even see a change through that little window, but it smokes a little bit on start up. 8000 miles on the engine. Thanks for the comments. I'll be sure to give the results when I get the seals replaced. By the way, any tips on getting in there and replacing the valve stem seals would be greatly appreciated. I got the manual, but would also abide any advice.

Re: GZ250 Smokes on cold start, stops smoking after running
 

The bike runs well and has good compression. Little to none oil consumption ! Could it just be moisture build up from a parked situation and then a burn off of the moisture. All it takes is condensation in the exhuast system and it goes away as the system warms up.

Re: GZ250 Smokes on cold start, stops smoking after running
 

This is not a true correct comment. There is different types of "smoking" issues. There is different suspect components.

When your engine only blows a small amount of smoke out the exhaust after startup but then the smoke stops, you have a bad valve stem seal(s). If your engine smokes most all the time under acceleration then you have bad rings. The reason your bike only smokes for a short period is that while the bike sits in between rides the oil is dripping past the valve stem seal into the cylinder. When you fire the bike up, the combustion is also burning off the accumulated oil in the cyl. Since the leak is very minimal, after about a min your engine has burnt off all the residual oil and is now running clean.

Re: GZ250 Smokes on cold start, stops smoking after running
 

do it right 58k now going on 80k tear it down needs valvs seals & if u ge down futher you may see more parts waren out cam guides carb oring to head I was lucky I had a crack in the spark plug hole so what i did took every thing down to the base & build it back up with factory parts thats how its done the the right way even a new clutch & stator

Re: GZ250 Smokes on cold start, stops smoking after running
 

Please make use of the time honored punctuation we all learned in school. We would have less trouble reading your replies and comments.
Now read this slowly and remember I am normally very polite and will always try to show respect to all forum members no matter what the issue.....BUT
YOU ARE REALLY STARTING TO PI$$ ME OFF!!!

I don't care who you are, what you are or why you are but you don't join up to any forum and tell everyone they are wrong and only you have the answers to all situations that arise. Do you think we are all beginners with absolutely no common sense or experience? The combined knowledge of this forum is awesome and we trouble shoot problems of every kind without a major rebuild as the only solution. All parts and products need not have a Suzuki label on it to work properly and reliably.
Your idea of maintenance and repair is bordering on insanity and you might need some better meds as soon as possible. Oops, I may be wrong.........you already know what is best for your particular ailment.

Re: GZ250 Smokes on cold start, stops smoking after running
 

Hey WW, have you noticed that mrgz250 has only been a member for 3 days, and all he's done is piss everyone off. I'm rapidly coming to the conclusion that he's just a troll, trying to cause arguments. Let's hope he vanishes up his own ars*hole in the near future.