i just got a used 00 400ex and i would like to make a couple of mods. i already drilled some holes in the airbox and i ordered the xr 250 cdi box. what else would anyone recomend to do, i might get a 440 kit from white bros in the summer. does anyone have one that could give me a review on it
thanks



00 400ex stock except for skin graphics

 

get a k&n filter and prefilter,and jet accordingly,an aftermarket exhaust system.i run
the big gun on mine.you'll see a nice bottem end
difference with these mods.

 

First off don't go 440, go 416 or 426. they are faster than a 440. the 440 gets more torque, thats all. Yeah go filter and jet accordingly. Buy a good pipe. Not mass production pipes thats fmf, dg, white bros, big gun, double barrel. and its best to get the pipe of the engine builder like ct 426, ct pipe or tc racing and sparks and even four stroke tech. It may be more but you will be happier in the long run becuase they can build the kit and match the pipe. its also easier to jet and give trouble shooting tips if you have all their products.

 

thanx alot dirtdemon i went on the ct site and there was no 426 kit i might just go with the 416 do u know if the come with a sleeve ?
does it require boring out the motor?

 

Only the 440 needs a sleeve. The 416 and 426, they bore out the factory sleeve.