Jetting Question

[roamer9562]

Just put on an HMF Powercore 4 Pipe with a powerbomb header pipe and a uni air filter with filter box top off. Need to know a good starting point on main jet for Utah elevation on 2005 400EX.

Any info on this would be greatly appreciated... If anyone knows where I can get a chart for jetting would be great too.

thx.

Roamer

05 400EX
HMF Powercore4 Exhaust
Powerbomb Header Pipe
Uni Air Filter
14T Front Sprocket

[jcs327]

What elevation above sea level are you?. If you don't know, the local airport can tell you. If you are below 5000' I would suggest 42 pilot, 155 main, 2 1/2 turns out on the fuel screw. that should get you fairly close. If it surges or backfires in midrange, go up on the main. if it bogs, go down on the main. hope this hepls. jetting is a trial and error thing if you don't have an exhaust gas analyzer. whats perfect for one machine may not be for the other machine, but they should be close.