smoking '00 426

3 replies to this topic
  • TommyT882000

Posted February 18, 2002 - 06:11 AM


When I start my bike up It will puff a faint bluish smoke almost like a 2 stroker but, not nearly as bad. My first thought was oil! So I kept checking the oil level. Nothing ever changes. Then I noticed that after the bike completely warms up the faint smoking quits. Only time that it does this is the first start of the day. Anyone had this problem? Anyone have any ideas?


  • sirthumpalot

Posted February 18, 2002 - 08:10 AM


This is one typical symptom of worn valve stem seals on a 4-stroke. When the bike sits the oil seeps through and onto the valves. When you start it the oil that seemed through burns off, but not enough seeps through while it's running to cause any visible smoke.

I also remember reading something here a while ago that suggested that this may also be caused by a worn out piston/cylinder. Aparently it's possible for the piston to rock back and forth a bit when cold and as it warms up and expands it gets tighter and doesn't rock as much and less oil can get by. This is new to me but it sounds logical.

If it's got a log of hours on it then it may be worth rebuilding the whole thing anyway.

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  • MikeOK

Posted February 18, 2002 - 10:30 PM


Give us some history on the bike. I rebuilt mine recently so it's still fresh on my mind. I had a similar problem, but it's good to go now. Sounds like valve stem seals though. No big problem...

  • TommyT882000

Posted February 18, 2002 - 12:02 PM


Bike history: In 2000 I rode maybe twice a month. In 2001 I broke three ribs the first race of the year and didn't but three times! Pisser huh. Oil has always been changed and stuff like that!

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