Hesitation problem

[brian400ex]

I have a stock 400ex. It has a T4 silencer on it and a Uni filter. I put a 160 main jet in it and moved the needle up one notch. I noticed a slight hesitation reving it up in neutral. I never messed with the pilot jet. If i moved the air screw a little would that help? Which way? I did a plug test and it looked good, a little black on the inside, but brown at the tip.

[Wheelie]

Try stepping up to a #40 pilot.

[brian400ex]

What is stock? Do you think i'm lean?

[Quadracer5]

I run a Pro Circuit T4 also, but with a stock filter. I run a 155 main, stock needle position, stock pilot jet and it runs perfect. Also, I turned the air/fuel mixture screw out 1 turn further from stock

Kyle

[brian400ex]

I messed with me air screw and i think that fixed it. I couldn't tell it hesitated when i was riding just when i revved it up really quick in neutral.

[crashinmatt]

yes ur lean on the pilot. like u said u turned it out and it helped. but if u need to go more than 1 turn, then u would be better off goin up a size of the pilot jet. then u have to turn it in and adjust it from about 1 turn out from all the way in.