Question about 2003 Yamaha YZ 125

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Yz 125 2001. starting ploblem after top end rebuild

Yz 125 2001. hi i have rebuilt the the top end on the bike and all seems to be fine with compression etc. Now attempting to make the first start the bike wont fire. there is fuel coming out of the overflow pipe of the carb after every kick. checked for spark and its working fine. any help please. thanks

Posted by wezz2811 on

  • devincadell
    devincadell Nov 25, 2013

    dont give it so much gas if the choke is on just kick it or maybe take your carb off and set the float right



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Kinda sounds like your needle valve is sticking in your carb and it is giving it to much fuel

Posted on Jun 03, 2010

  • Anonymous Jun 05, 2010

    Did this help you out?

  • Mista B Apr 07, 2011

    Now i had the same problem with my bike a few weeks ago. Got 3 of these bikes and this one always does this after a top end build. Got spark, fuel, loads of compression but just wil not fire. The other two bikes start up fine every time.

    Solution, towed it for about 100 yards with the Van and boom, off it went. Let it clear and settle down for a while, then shut it down. Let it cool and it fired up first kick no problems. It has fired up first kick everytime since. Weird one, but always does this and still never worked out why.

    Mista B.



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