CR 500 motor ??

[SnowRacerX]

Anyone drop a cr500 motor in there 250r?? What is involved in doing this? I'm building my 250r for the dunes and i need a new motor so i was thinking of it.

[wvspeedfreak]

You don't wanna do that.It will vibrate your teeth loose.:D

[nacs400ex]

Originally posted by SnowRacerX
Anyone drop a cr500 motor in there 250r?? What is involved in doing this? I'm building my 250r for the dunes and i need a new motor so i was thinking of it.

Theres no counterbalancer in the cr500 motor. This will cause your whole bike to vibrate. Without some inventive fabrication the frame will crack from vibration and you wont beable to feel your hands afterwords. I have seen some people try rubber mounts, but it doesnt do.

Something you might want to look into: I have seen 500cc big bore kits for the R. The kit allows you to bolt on a cr500 head and maintain the 250rs counterbalancer. The 450s should would have a hard time catching an R with that kit.

I tried doing a search but couldnt come up with the companies name, maybe somebody can help you there.

[beak7707]

Patriot racing makes the 500cc kit. I have seen some cr500 conversion that looked pretty good on this website and others, and some people say they are great. But nacs is right that thing will vibrate like mad. I dont know if quadzillas have counterbalancers or not but the vibration from those is unreal. I think you would probably be happier with a big bore motor. You can do a search on here about the cr500 motor, a bunch of people have talked about it.

[easystroke]

Try this place. sabertooth racing (http://saberracing.com/) I sure wish I could get one of those setups. The quadzilla does have a counterbalancer also.

[baker250r]

i know a guy who has a cr500 in a 250r setup.... he ice races it. is frame isnt a 250r anymore tho... he has bars welded everywhere to reinforce the thing... and it looks really gaudy he had to get a pipe custom made by CT.... wich cost him 900. he also says it is a pain in the anis to start when its cold out. i would get a big bore kit too....

[kwatts400]

http://www.atvsource.com/articles/product_reviews/2002/011602_mac_racing.htm

Try this one.

[joedirt]

My Bro did this conversion a while back. I wouldn't do it if I were you. Alot of fab work. Nothing runs like a 500 though. He raced it once and yes it will track down a 350pv motor. Vibration is bad though you really can't rev the motor.

[XCredrider]

why not put a really big 4 stroke KTM motor in it. Those are supposed to fly and ive seen them on bikes and they do. Daryl Rath used to use one and dirtwheels said that that motor should have been put in a quad to start with. And it shouldnt vibrate to bad. jmo :D

[baker250r]

Originally posted by XCredrider
why not put a really big 4 stroke KTM motor in it. Those are supposed to fly and ive seen them on bikes and they do. Daryl Rath used to use one and dirtwheels said that that motor should have been put in a quad to start with. And it shouldnt vibrate to bad. jmo :D

yea, and u can spend i think 3 for the motor alone..... but it would be one awesome quad.

[Mechanix311]

I have built two trx500r's and they are both a pain in the butt. They are hard to start and i mounted mine on lots of nylon and it still vibrates like no other. They take alot of fab work and if you cant weld or be creative than dont even try it you will be dissapointed. When they do run they scream though. The one i own right now has an ftz drag pipe 39 pwk carb and is ported. It really flies whenever i can get it started. I have not broken my frame yet but i have taken extra precaution. Im in the process of selling it because it is too much work. Just some advice.

[pro6]

I have a 250r with a 400cc pilot jug on it. I've beat a many 350 pv's at the dunes. I also tt and short track race. FTZ and Trinity builds them I know. But I wouldn't mess with Trinity Racing. Call FTZ. They also make a 370 pv now that is supposed to put out more hp than the 400!