How can I get better throutle response from my 450

How can I get better throutle response from my 450exc? I just road my 2003 for the first time and i had a small delay in the response. I ride mostly in Southern Ca. At an averge of 4,500 ft. What is the right jetting for my bike or what jetting do you use to have your bike in good shape? Thanks for your help. :)

It takes a little time to get the jetting perfect. Ask JD in the jetting forum for help at your altitude. The BK mod for the accellerator pump will shorten the squirt time from about 4.5 seconds to 1 second for much better throttle response. My settings are: BK mod, OCEMN needle at 4th clip, 170 main, 45 pilot, 2 turns out on screw; adjust for temperature. (Midwest altitude)

Buy the JD jet kit! I did and I'm very impressed, it works!

I even paid retail for one!!!


jet it and run the power now mod

jet it and run the power now mod

Agree 100 %

i ve also heard great things about the icat system. I m told by my shop that it took all the jetting issues out of one of their race bikes. They say the thing rips now regardless of where they run it now.

By trading your KTM 450 for a CRF 450. Sorry man I could not resist. Seriously though!! :)

I too ride in the deserts around socal and run 42(stock) pilot 2 turns out, OCEMN needle 4th clip and 172 main. So far she's pretty good.

I am going to do the BK mod this weekend as I know the AP squirt is killing me. Hope this helps ya. :)

The BK mod for the accellerator pump



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