Honda 400ex more power

hey everyone,

i have a 400ex with fmf power core exaust, k&n air filter, jetted, and eliminated the airbox.

i need more out of her. what should i get?
440 big bore
426

i mostly ride the dunes and fast trail riding.
thanx for the help.

tfred

The 440 kit will probably be the best kit for the EX

Agreed, also, a cam upgrade,higher compression, port work and a bigger carb will go nicely with the added displacement.

sprocket size changes will give you more grunt in the lower end but you will lose top end speed ... or vise versa depending on the sizes you use ..and its cheap ...

440 deff!!!