please help jetting HMF exhausts

[woodsridn400]

I have 2 stock 400exs there 07 and 05 the 05 is a slip on hmf I have jetted at 40 and main 160, it has no header mod, lid on, k and n filter. Seems to be ok do some of u think that's too much?
My real problem is my 07 I have jetted at 40 and main 165 now it runs awesome untill your high rpms and it starts to cut out. Anyone know if the cutting out is bc or to big of jets or needs more? This has an hmf full system k and n filter, sparks advanced key, lid on And spark arraster out.
Thanks for any input from anyone riding this weekend and don't want to have it messing up while I'm out. Also I live in ohio not sure about elevation leval etc

[jayman63]

im no expert, but i have an 07 with a hmf slip on and k&n. I just emailed hmf and told them my setup, they respond quickly with jetting suggestions. they suggested i run a 40 pilot and 152 main. they also suggested i run with the lid off. i think it runs much better with the lid off or some sort of lid mod. i have an ehs powerlid kit and love it. hope this helps

[woodsridn400]

Thanks for the input. I know they run better with lid off I ride more muddy places and woods. So I like to try to keep lid on, I've looked at the lids that flow better just a lil pricey

[-TheDude-]

i emailed hmf a month ago with my set up for suggestions and they never emailed me back

[jayman63]

i got an answer back the same day. try this guy

mike@hmfengineering.com