07yz450 smoking.

5 replies to this topic
  • crila18

Posted October 12, 2014 - 12:23 PM


I got a yz 450 that whenever is cold it smokes a lot " bluish smoke" once it gets hot I does not smoke any more. Can someone help me find out what's wrong with my bike .thanks in advance

  • crila18

Posted October 12, 2014 - 12:35 PM


No I did not but when I started it, it really looks like a 2 stroke bike

  • billygildark5007

Posted October 12, 2014 - 06:54 PM


Blue smoke means it's burning oil. Likely culprits are the piston rings or something in the valvetrain allowing oil to enter the cylinder like guides or worn seals. A leak down test would tell you more if you can do one.

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  • crila18

Posted October 12, 2014 - 06:58 PM


Thanks for the help .

  • grayracer513

Posted October 13, 2014 - 07:07 AM


Oil smoke on start up only (clears out when warmed up, doesn't smoke under a load) is normally an indication of a valve guide seal(s) leaking.

  • crila18

Posted October 13, 2014 - 08:15 AM



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