Buddy has a 2002 650 prarie and was having touble at low speed when he would go to take off it would stutter and and not work right. He took it to the dealer where they set the valves which were out of specs and carbs. He took it home and is still having trouble it is missing at an idle and very low speed, even after it is warmed up. Anyone know what may be the problem. Coil? Thanks for any input.

 

Pull out plugs and see how the carburetion is first.