cr500/250r help

[bada440ex]

will a cr500 topend bolt up on 250r cases

[hondaboy400ex55]

from what ive heard yes!

[Iliketogofast]

The bottom end probably wont last long if it does fit.

[bada440ex]

why

[Iliketogofast]

The rod and crank were designed for only half as much force as what you're putting on to them. I would replace the crank/rod when you do it... That is, if it fits.

[buddha440ex]

the cylinder will mount to the cases.. but then you are going to have to get a different crank for the bottom end or it will just destroy it..

[250R-Dee]

You will also need to machine the cases since they are meant to me used with the 250R's bore. There is a company that has been doing this. I have a link to thier site on my home computer.

[250R-Dee]

MAC racing is the company that did the 500R cylinders on 250R lowerend mods but their site is down. You can find info about them on ATV Source.

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

[Iliketogofast]

Hmm.... What kind of money would I need to machine the cases and get another crankshaft? Does the rod from the 500 Cylinder work on the 250R Crank?

[Eddiesanders250]

That cyl would destroy that bottom end. send it in to a reputable company to have them go through the bottom end and replace anything that looks like it needs to be. I would not just bolt that cyl on the stock bottom end.