06 yz450f idle issue

5 replies to this topic
  • seacraft69

Posted February 22, 2014 - 02:01 PM


Hello. New member here. I bought a 06 yz450f on monday and finally got to ride it today. It runs really good everywhere except it wouldn't idle. So I turned the idle adjustment screw in and brought the idle up, but when I did I noticed gas started coming out one of the vent lines. So I screwed it out slowly and the idle got slower and so did the gas flow. I finally got it where no gas was coming out the vent but the ldle is very low. Any ideas? And thanks for replies

  • grayracer513

Posted February 22, 2014 - 07:38 PM


The only thing that makes sense to me is that the float needle isn't sealing well, and the pitch of vibration at a higher idle speed is causing the float to bounce around enough that it leaks a bit, then floods. 

  • seacraft69

Posted February 22, 2014 - 08:13 PM


That makes sense except for the fact that when I barely touch the throttle it will sit and run at about what the idle speed should be and no gas is coming out the vent line. Could it because of the po adding an fmf 4.1? He said the bike is stock except for the pipe and a 51 tooth sprocket.

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  • Will.A.R.

Posted February 23, 2014 - 06:09 AM


+1 on gray. Check the valve. I've had that happen more than once.

  • grayracer513

Posted February 23, 2014 - 08:10 AM


Could it because of the po adding an fmf 4.1?



  • seacraft69

Posted February 24, 2014 - 09:52 AM


Ok ill check it out. The po gave me a carb rebuild kit that looks about half there. I'll check when I get home to see if the float needle is in there. And thanks for the responses.

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