Give it throttle, it dies

2 replies to this topic
  • ryan2214

Posted January 30, 2009 - 02:43 PM


Just got done putting my 1999 yz400f back together from an almost complete top end rebuild. It started right up. I let warm up for about ten minutes then as soon as I give it the smallest amount (I mean very little) of throttle, it dies. No pops, no weird noises, just dies. The carb was torn apart, re jetted, cleaned out, during the rebuld. Any ideas of what it could be? Something stuck in the carb or maybe a problem with the rebuild?



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  • grayracer513

Posted January 30, 2009 - 02:57 PM


Something stuck in the carb sounds like a good bet. It would be in the main circuit, as in the main jet, a needle out of its clip, blocked main air jet, etc. Since it starts and idles, the pilot circuit seems OK. Another possibility is the slide plate on the engine side of the slide may have gotten inverted. The flat edge with the hole goes down.

  • buzzfin

Posted January 30, 2009 - 05:02 PM


Might want to check your accelerator pump too.

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