03' YZ450F Jetting

1 reply to this topic
  • curtis515s

Posted November 22, 2004 - 08:23 PM


I have a 03' YZ450F that is stock with the exception of a FMF Factory 4 slip-on. Does anyone have any recommendations as far as jetting goes. It has been around 65 degrees here and at close to sea level. It tends to backfire right after you chop the throttle on a long straight. I think it's a little lean. I think it's the pilot but I just switched to a 4-stroke and am confused.


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  • yzf450jack

Posted November 22, 2004 - 09:07 PM


Turn the fuel screw out 1/2 turn or so . No more that 3 turns

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