New 04 450F Rich at 1/4 Throttle

2 replies to this topic
  • jdd123

Posted July 16, 2004 - 08:14 AM


I just bought a new 04 450F. Great bike. The dealer cannot jet, etc. I am at 5000ft. and have the pilot and main jets dialed in. On the needle at 1/4 throttle it is very rich. However, above 1/4 throttle, it is ok. I tried stock needle at stock clip. Then went 1 clip lean wich was better. There was no difference between clip postions 3,2, and 1 (all the way up or needle all the way down lean).

It is just this one spot at 1/4 throttle especially in 1st gear that the bike doesn't run steady and the power jerks. It is definitely a rich condition. I am thinking of going with a leaner needle on the shaft or daimeter since the manual says the shaft affects throttle from 1/8 to 1/4 while the clip affects 1/8 to 3/4.

Any suggestions?

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  • Wyatt

Posted July 16, 2004 - 02:46 PM


You sound like you are on the right track..Even near sea level where I am, I had to lean the needle one position to make the power smooth at those types of throttle openings.

I never felt it when running hard, just when going slow at partial throttle openings.

  • jdd123

Posted July 17, 2004 - 06:09 AM


I tried leaning one position. It was better but still there. But leaning 2 or 3 positions made no difference.

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