Well i am racing next year in gncc. I want to build or have someone build me a fourwheeler. I want to have a 400ex w/no engine and put a yz450f/crf450 engine in it. I dont know what class i would race if i do this but im sure there would be a class. So anyways How hard would it be to swap a crf450/yz450f engine in to a 400ex frame with the stuff from eastcoastatv? How hard do u think it would be easy,medium,hard? And would this mean thing be aloud in gncc? since a 800 praire races in the utility class? and 660 raptor races pro production? please help thanks

 

Kevin1422- I dont know if either one of those motors would be good for the GNCC's. I think you would be better off with a 400ex motor, the new Kawi, the new Suzuki or a Cannondale. But to answer your question I have had 3 different friends do the 400ex/yz426 conversion. One of them did it through ECATV and the other two did it themselves. If you know what you are doing the project would be a medium in my opinion. Time will be what you need the most cause it will take awhile to get it all done. If you dont really know what you are doing I would say it will be hard. Well I hope this helps and good luck with whatever you do.

 

I really dont think it would be that bad. because it would be kinda like a 250r.

 

Yea but a 250r motor is made to pull a quad because it is a quad motor. yz426's and crf450's are made to pull a dirt bike. In the tight woods I dont think it would be good. If it was a good idea you would see the pros doing it.

 

yea you are rite about that. But how about a 250r what class would i race in? But dont i have to put alot of money into one?

 

Kevin, there is plenty of room for a YZF or CRF450 motor in a 400EX chassis. The rear shock mount is kind of in the way of a good airbox setup though. You have to come out of the FCR40mm carb "up and over" the shock mount to get to any airbox. Not the best flow but it still hauls.

 

Here is a frame made to have a CRF450 in it.
Here is one for a YZ426
I'm not sure if they make one for a YZ450, but it might be the same as YZ426?

OutCast
88 LT500RJ

 

hey just ask captain carl, he's got this one all figured out.