missfires at 7500 rpms to 8500

[m.collins]

i have a 03 600 and on high rpms it pops, srarts missing at 7500 rpms to 8500. you can can clutch it and get it above this range and it's ok. where do i need to start. tune up is good fuel filter is good...and it does have a k&n air filter..

[noglo]

Try swapping the k&n with a stock filter, it's hard to get the carbs tuned with a k&n.

[DreKat]

K&N filters and Kats dont mix