Does any one have hotcams on there 400, if so was there a signifcant power gain and where? I got the intake and exhaust cams and had them installed at a suzuki dealership. the only thing they did was make my quad slower. I know the cams made my quad slower becasue i went and raced my buddies kfx-700 that i usually beat and i got walked on. The cams made my quad slower. I had the lash and clearence looked at again. But i think the tech had to much pride to admit he could of made a mistake. I had the cams uninstalled and my quad was fast again.

 

My son just finished his KFX 400,big bore kit,quicksilver carb, 400 ex carb boot hot cam on intake side only I will check with mech. this set up really increased the power, not sure why he used intake cam only,will let you know

 

I asked grew at cwr about cams for a kfx 400 and he said first replace the stock carb. the stock carb is way to restrictive. He said using cams with the stock carb would be like drinking a milk shake out of a coffee straw. He said edlebrock makes a carb for the kfx that fits directly into the existing carb boot, and it will flat out pull your arms off. (the carb is expensive around $480)

 

So what size carb should i go to. mm wise. Also, why do the cams make breathing threw the stock carb so difficult. People have said it makes there quad faster but i had no luck. Mine was faster with out hotcams????????????? The stock carb is that restrictive?

 

huh!!!!!!

 

i believe it is a 38mm, but i am not positive. the stock carb is that restrictive though, in fact i believe using the 400ex carb you get about a one horse power gain. Call greg at CWR and he can hook you up on the best mods, he mods kfx's for people he races against. he himself races a mojave that runs around the high 40's to low 50's in horsepower