Jetting on a 03 450?

1 reply to this topic

Posted November 30, 2004 - 06:35 AM


Bought this bike and to my knowledge the jetting is stock. I noticed that when at idle if I crack the throttle open fast it will cut out. Is this normal for 4 strokes or can adjusting the air/fuel screw help that out?

Also this weekend it was in the 40's(in va.) and it felt like maybe it was not pulling up top like it should(in 4th gear)

The bike has so much power I have been scared to fool with it. Is the stock jetting pretty spot on or can I improve it?

Thanks for the help. :cry: :cry:

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  • Butta

Posted November 30, 2004 - 07:22 AM


With the colder air, you are probably running lean. Try turning the fuel screw out (if you don't know how far out it is, screw it all the way in, counting the turns, first, then screw it out to around 2 1/2 -3 turns). If you are lean on top, then you may need a bigger main.....stock, from what I have heard, is pretty lean.

Anyone else?

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