full exaughst(hmf,fmf,whit bros, etc...) k&n airflter(no airbox lid) sprocket setup, 416 big bore no bigger than that, 450r front shox, tires, race fuel.
make a 400ex faster put a intake, jets, cam, piston recomend a 416, and take some things off that are heavy
400ex is faster
trx 400x
run a smaller sprocket on the rear
of course a 250r is because its a 2 stroke and bigger cylinder
stock to stock my buddy has a z400 and i have a 400ex and me and him are the same weight and we are side by side the hole time and they both will go about 70mph it depends how much weight you put on the quads
how to time a 2002 400ex
400ex does 60 tops.
Have you even rode both four wheelers? The kfx is much faster. It has better bottom end, and a great top end. The kfx 700 is over all the faster fourwheeler.
the stock 400ex has 29.3 at 6900 rpm
definitly
The 400ex its got a bigger motor... :P