crf450 motor in a 250r frame?

[HippieMcgrath]

I've seen the crf hybrids on here and might atempt it. I'm a fabricator so It shouldn't be too hard. My question is, Will a crf motor fit in a stock R frame? They do it to the after market frames with stock geometry, so it would work right? I naturally would like a chromoly frame for this project but I have a extra r frame. Besides if I do it to my r frame and then buy a chromoly frame the new engine mounts will be easy to change it over. Sure I could sell my R and all my stuff and buy a trx450 but, then you gotta buy new arms swingarm and everything else. If I do the swap on the R I don't need to buy anything. Any help is more than I have now. Thanks Doug

[250x_kyle]

no. frame rails on aftermarket frames are higher. the stock r frame isnt high enough for the crf. plus the stock are frame will rattle apart even after gusseting. just spend the extra penny on an aftermarket frame it will save you in the end.

[HippieMcgrath]

I didn't figure the stock frame would take it, but was wondering how it works in the aftermarket frames? They are supposed to be the same geometry as the R. Or do they make the frames a litltle taller when you order a hybrid frame? I want to continue to use my R stuff but I might try a 450r engine swap some time. In a aftermarket frame of course.