Winter Jetting?

6 replies to this topic

Posted December 05, 2009 - 09:32 AM


I want to get my 450 ready for winter and I have been running the JD kit all summer with great results. Its now cold out and the bike popps and stutters really bad. So do I just swap out the red needle for the blue needle and keep the same clip settings and jets in? Or DO I change those too? Thanks.

  • mxrayser

Posted December 05, 2009 - 11:22 AM


Try it and see if its better, but you will most likely have to change at least the main

  • mxrayser

Posted December 05, 2009 - 11:24 AM


Usually a couple sizes up or down on the main works for seasonal jetting for me, but I;m in California, so no great temp changes

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Posted December 06, 2009 - 01:17 PM


Thanks man, Too cold to really get out and try any of the changes, but so far just swapped out the needle and it started more gracefully *less popping*.

  • tmoney302

Posted December 07, 2009 - 09:05 PM


The popping your experiencing is probably when coming off the throttle which in that case you can richen up your idle/mixture screw by turning it out till the jake brake noise quits. This will also help it when starting. For the main jet, you don't need much. Maybe up it 5 or 10. When ice racing, I run a 180 from a 165 on my bike and thats plenty rich enough for me down to -10f at sea level. You'll notice the biggest improvement from cleaning up the idle mixture though.

  • CaptainKnobby

Posted December 07, 2009 - 09:10 PM


during the early part of racing season here in VA. like 1st week in march it is really cold on that sunday. My 06 would do like yours in the cold but I would just turn the fuel/air screw out about a couple of turns and it would clear my 06 up.


Posted December 07, 2009 - 09:14 PM


cool thanks, Ill give it a shot:thumbsup:

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