i bought a set of hope mini x2 and thought i could use them with my old 160 avid rotor's...but no can do, i have a postmount fork aswell as postmount calipers but i got a pair of 160 and 185 mm rotor's but none of them will work ??
what am i doing wrong ??
Well, the 185mm definitely won't work without an adapter. Generally front brakes/forks are setup to run 160mm; and anything else requires a manufacturer specific adapter. My rear post mount is setup for 160mm; but as the other poster said, there may be occasions where a rear mount is setup for 140mm. What mount are you using for front - IS or post? And then like the other poster said, what exactly is the problem? "Not working" doesn't give us enough information to tell you what's wrong.