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Dark_Stang
11-26-2006, 07:20 PM
Yesterday morning I started my 400ex up and it started smoking. I mean, A LOT of smoke for about a minute. It hasn't done it until then and it didn't do it today when I started it up.

Anybody know what might have caused it?

Thanks.
400eXr1d3rZ
11-26-2006, 08:12 PM
What color was the smoke?
Dark_Stang
11-26-2006, 08:14 PM
Smoke was white and smelled like oil.
400eXr1d3rZ
11-26-2006, 08:26 PM
White smoke is usually steam, hot air to cold makes steam. Bluish/purplish smoke is oil burning, could be valve seals, or in a worse case...worn piston rings. Black smoke is carbon.
Dark_Stang
11-26-2006, 08:34 PM
Smelled like oil though...

I thought valve guide seals too, but it didn't do it today when I started it. And I don't think it's the rings because it isn't a constant smoke and it isn't leaking compression according to the "park on a steep hill in first gear" test.

Could it have been steam? Out of all the bikes that went mine was the only one that did it.
400eXr1d3rZ
11-26-2006, 08:43 PM
That's the only explanation I can think of. That's the only reason (that I know of) that white smoke would occur.
rooster300ex
11-27-2006, 07:23 AM
If the valve guides are worn then the longer the quad sits the more time it has to leak oil through the valves on top of your piston. and when you fire it up it burns the oil off the top and quits smoking.
400exfan19
11-27-2006, 09:08 AM
ive had it where i just cleaned my air filter and it was still wet, i started it up and for about a minute or two it was smokin like crazy
400eXr1d3rZ
11-27-2006, 03:25 PM
Originally posted by 400exfan19
ive had it where i just cleaned my air filter and it was still wet, i started it up and for about a minute or two it was smokin like crazy

Water does that.
Dark_Stang
11-27-2006, 03:48 PM
Originally posted by rooster300ex
If the valve guides are worn then the longer the quad sits the more time it has to leak oil through the valves on top of your piston. and when you fire it up it burns the oil off the top and quits smoking.
Right, but it had only sat overnight.

Okay, so if it was somehow steam, why did it only happen to my bike? There were three others in the same conditions.
xxnightraven73x
11-27-2006, 04:08 PM
chances are if it smelled like oil it probably is your valve seals thats the way mine started out smoke on start up(white which means they arent too bad) then it was real bad when i opened it up(turned blue which means they were shot) but i let them go for about a month before its was tooo bad i did the seals and it hasnt done it since.cheap and easy fix
2muchquad
11-28-2006, 12:38 PM
Mine smokes for a few minutes when i start it up initially,new top end earlier and new valves seals.Im willing to bet its the valve guides themselves they may have those o rings under them that are shot.Runs like a scalded dawg so for now i'll live with it until i change the motor;)
bwamos
11-28-2006, 01:09 PM
Originally posted by 400exfan19
ive had it where i just cleaned my air filter and it was still wet, i started it up and for about a minute or two it was smokin like crazy

Umm.. I hope you dry the filter and oiled it with K&N (or gause type) filter oil before you ride it.

The reason you got white smoke that smelled like oil.. is because the intake air filter was WET, and probably had filter cleaner solvent in the water that was burning.