on my 450 if i very quickly push the throttle all the way and then let go right away it will die on me or try to die. what is my problem?

 

any advice greatly apreciated!

 

has it always done this or did it just start?

 

it just started but i just took my airbox lid off and have a k&n air filter and a complete big gun exhauhst system, i have the needle at the bottom clip and a 182 main jet, 48 pilot jet, and the mix screw about 3 turns out

 

Perhaps, your jetting just isn't quite perfect?

Also, there is an overflow (can't remember what it is called exactly right now) that keeps it from flooding out (returns excess fuel back to the bowl), some of my freinds have had to go bigger on that overflow.......