thats what i'm running, an '05 trx450r rear shock, prolly sane as a 400ex, but a pain to install, i had to cut off the right front, rear fender mount, and my airbox almost rubbed a hole in the rezzie, so i had to get a cfm airbox, but it rides like a cloud, awsome shock if you want the hassle of puttin it in, oh and ken oconnors shock bushings work great with it
see pics in my albums