Fuel screw/fuel mixture question

1 reply to this topic
  • AKmotoXrider907

Posted August 13, 2014 - 07:59 PM


Hi I wanted to know some signs that my fuel mixture might be too lean or rich. I know that backfiring means it's too rich?? Maybe? Any help is appreciated!

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  • grayracer513

Posted August 15, 2014 - 12:32 PM


Exhaust backfire is normally a sign of a lean (not rich) idle, but it can also mean that there is an air leak in the exhaust, commonly at the header/midpipe joint, but possibly at the head as well. Check that before you mess with mixture.


Excessively rich idle is prone to stalling when the throttle is chopped suddenly under a moderate load.  Lean idle tends to "hang", or drop back to idle too slowly when released.


Read: http://api.viglink.c.../jetting.htm#PJ

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