Has anyone heard of any places that specialize is hop ups for the crf 450. I have a brand new engine in a 400 ex frame. It has a Baldwin pipe and kn air filter. I just ordered a stage 1 hot cam for it. That is all I want to do until she starts to smoke and then it will be time to build a monster engine. I know of alot of places that has big bore kits but I want to know if anybody had tried any or have any friends that have tried any. thanks

 

hey whats up? i have a 400ex and i wanan upgrade it to the crf450 engine... where can i get an engine and how much $$$ am i lookin at? is it a big difference in speed?

 

I bought my bike with the crf engine already in it. Luckily it was like brand new. It had only been started 3 times. The guy I bought it from bought a brand new dirt bike and new 400 ex. He then took only the motor from the dirtbike and sold the rest for parts. He sent it to a racing company in Calif. specializing in conversions. I want to say Walsh racing but that may not be the place. Some personal issues came up in his life and I ended up trading for the bike. I have seen ads in the back of dirtwheels mag about purchasing a crf 450 motor but it cost a couple of thous. As far as conversions, I would say post a message asking info about them. I could give the guy a call and find out for sure where it was converted but it could take a couple of days to reach him. You ask how does it run, I have 4 friends with YFZ's. All have pipes and filters, with the cam mod and we all are running dead even in a 300 ft drag. My bike is stock except for the baldwin pipe and kn filter. Just imagine the trx 450r with a higher comp. pistion and cam mod. That would essentially be a crf 450.

 

My YFZ's run quite a bit better than my CRF450 quad ever did.

That motor costs around 3 grand. Not worth it now that 450r and YFZ's exist.

 

He is right about the cost of building a crf 450. It really is not worth it considering the trx 450r and the yfz 450. I race pro class MX and can honestly say that every yfz I have raced can not pull my crf. The yfz's mods include: one with a GYTR pipe and filter, retarded cam, another with a Curtis sparks pipe and filter, another with a Ron Woods pipe and filter, and another with a FMF pipe and filter, retarded cam mod. There is one Yfz with a higher comp. piston that will consist. beat me 2-3 bike lengths in a drag. Now I know the trx 450r is much slower than the crf and yfz but what I have seen, the yfz does not outrun the crf. Maybe your crf was an 02 or had jetting problems etc. Also, gearing is a big issue. The crf sprockets are too high geared. You must order a 12 tooth front or special order a bigger rear from someone like sidewinder sprockets.