09 450 jetting

5 replies to this topic
  • cjxrider125

Posted December 03, 2009 - 12:36 PM


im having a lot of popping on decel and i feel a hesitation when accelerating on my bike. everything is stock. have not touched a thing. i was wondering what jetting changed you southern california guys have made to get the bike running better?

i ride the motocross tracks in so. cal. (comp edge, racetown, pala) with the occasional trip to glamis

  • davbrucas

Posted December 03, 2009 - 07:47 PM


I have read that they come stock a little lean...try adjusting your fuel screw and get a larger pilot jet if needed.

  • FinchFan194

Posted December 03, 2009 - 07:51 PM


If your bike is popping don't you wanna richen the main not the pilot? or am I meant to always be wrong on here? I will learn one day!

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  • grayracer513

Posted December 03, 2009 - 09:56 PM


The main has no effect on decel backfire, as the throttle is closed during decel. The pilot is where the fuel would come from.

A certain amount of popping is normal, and indicates a correctly jetted pilot circuit. Excessive popping can mean either an air leak into the exhaust system (check that first) or lean idle jetting.

  • Family Man

Posted December 03, 2009 - 11:11 PM


Check out the pilot circuit sticky at the top of the jetting forum.

  • cjxrider125

Posted December 03, 2009 - 11:27 PM


Check out the pilot circuit sticky at the top of the jetting forum.

perfect :banghead:, thanks i didnt see that

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