Jetting? 02 426 w/FMF ti4 and mid pipe


1 reply to this topic
  • flapwick

Posted October 04, 2009 - 06:39 PM

#1

Threw on the pipe and went riding at my local motocross track today.Felt like it had more useable power and speed coming out of corners.Nice.It felt like it was running fine....not missing,sputtering or backfiring at all while I was riding.But I did notice that if I twist the throttle while idling(not in gear),it responds beautifully initially,and then starts missing around mid throttle.I had a 45 pilot and a 168 main jet with me ,but it was soooo windy today that I didn't dare open the float bowl with all the grit whipping around to try them.Does anyone have any suggestions? Also ,a guy at the track suggested I mess with my air/fuel screw first.......your thoughts???Thanks.

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  • rdefonce

Posted October 05, 2009 - 09:09 AM

#2

[quote name='flapwick']Threw on the pipe and went riding at my local motocross track today.Felt like it had more useable power and speed coming out of corners.Nice.It felt like it was running fine....not missing,sputtering or backfiring at all while I was riding.But I did notice that if I twist the throttle while idling(not in gear),it responds beautifully initially,and then starts missing around mid throttle.I had a 45 pilot and a 168 main jet with me ,but it was soooo windy today that I didn't dare open the float bowl with all the grit whipping around to try them.Does anyone have any suggestions? Also ,a guy at the track suggested I mess with my air/fuel screw first.......your thoughts???Thanks.[/QUOTE

I agree with the guy at the track; adjust your fuel screw first.
Especially if it's running good now. you shouldn't have to change much, from the way you described it running.

Oh, and don't worry about the way in runs in neutral. Can't ride in that gear anyway.





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