i have a 99 sp 500 with a jet kit and it has a stumble.is only has it right at the idle when i give it gas .it doesnat matter where i put the air fuel mixture screw.so i wanted to change the clip postion on the needle.right now im on th forth slot down fom the back.i lve in south fl.thats where the kit said to put it.but if i move the clip will this help with the off idle stumble?if so do i go towards the tip of the needle or towards the back?

 

If you move the clip up it will lean it out if you move the clip down(toward the point) it will run richer. Try moving it up one notch....

 

I agree with moving it up a notch.

A good rule with carb tuning, is to make only one change at a time. If you make two or three adjustments at one time then experience a problem, it will be difficult to know which one caused the problem.

Good luck.