Need some help.

I have a 2012 ktm 300xc with a fmf gnarly pipe and a 165 main jet. My problem is from zero throttle to about half way in any gear the bike feels great. From half to full throttle the bike feels like there's no power. What do you all think? I can't figure this out.

Sounds like you need a larger main jet

No power, as in 'kill button', or no power as in 'gurgling/lurching'?


Have you cleaned your air clean? Power valve?

Edited by TheKoolAidMadeMeSick

Like its bogging down. Air filter is clean and so is the carb. I run 50/50 vp 110 and pump gas.

I am running a 168 main if it is below 60*. At temps above 80* it runs better with a 165.  A lean main will be down on power but extra responsive as well - not boggy. Is the fuel fresh and is the PV working correctly?. If premix sits for more than 2-3 weeks I can feel a drop in power.  Any more smoke than usual? If the reeds are original, the original Vforce4s had some problems, but it was more a problem in low to midrange power.

Crazy to say but could be to fat on the main.

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