I heard that there is a 500 kit (so to speek) for the 400ex. What is the biggest cc you can make the 400ex and what is involved? Cost etc.?

 

I have ridden a 480EX. I believe that East Coast ATV has one.

 

I am not sure on the 480ex I think East coast atv uses all YZF400 motors in their race bikes.

 

Mickey Dunlop of FOUR-STROKE TECH has produced a 500 kit for the EX. It was on the cover of DIRT WHEELS about a year and a half ago. I believe they are located in Maryland. The 480 kit is a product of TC Racing, I believe. There are other tuners who specialize in different sizes. CT and IMS both have 440's.[ I've got the CT ] Curtis Sparks has a 416 which is AMA legal and did very well last week at Red Bud grabbing more than a couple of holeshots. LRD does a 426 which is rated highly. The company I've been hearing a lot about recently is GT THUNDER in Ohio. Their 417 kit bike runs 14:1 and puts out over 45 horses! Some other companies to look into; Noleen, Pro-Fab ATV, Powroll, Duncan and Trinity. As far as cost, my engine work cost me just under $800. I already had a Curtis Sparks pipe. If and when you have engine work done, buy the pipe the tuner suggests. If you get ALL of your kit from one tuner, he will be aable to advise you on how to dial-in your bike much easier than if you buy 10 components from 10 different vendors. Good Luck and keep us posted.

 

static-x how fast is the 480? Can you compare it to a 426 or a 440 from your experience? Do you have sand nunes where you live? If so how does it match up against banshees on hill climbs, drags etc.?