05-10-2011, 03:31 PM
the subframes are not interchangeable from 250 to 450, other parts all fit, dual caliper, sprockets, etc. The CRF250X (not the R) has a heavier flywheel, lights, kickstand, electric start, and WIDE ratio transmission so you can hit the street or the lot. R model tranny is very narrow, makes it pretty much a straight parking lot bike once you gear it. X model requires no regearing to stunt and do slow circles, and 5th gear will still hit 70+mph