I have a 2008 trx 450r and I recently purchased a fmf power core slip on power bomb header k&n power lid and the k&n filter. I alos purchased fmf's power jet kit too but am not quite sure what I did wrong. I installed the correct size jets but when I hit the throttle all the way she bogs out. She runs fine at about 3/4 throttle and I back the air fuel mixture a turn and a half. anyone got any ideas?

 

Go with bigger main jets until the bog goes away.
I don't know what that means but the air/fuel mix screw is only for idle and just off idle and nothing more.

 

Take a couple minutes to read through the following link. Might not be your exact carb, but it fills you in on the basics.

Care & Feeding Of The Keihin Carb

 

Nice link ,thanks.