i'm trying to change the front brake pads on my voyager, and have no problem getting the calipur off, but cannot get the pad mounts off (don't know what they're called, but there's one on top and bottom that hold the pads in place). the issue, is that my largest socket is 21mm, and it is not big enough.

i'm guessing by eye-judgement, that it's 22-24mm for the bolt, but i want to be sure when i go get a socket for it. can anyone tell me exactly how large it is?

thanks!

also, how can i tell if my rotors need replacing?

okay, it's 23mm...again with the rotor question, though.

Rotors need replacement if they are scored from the brake pads.

Ideally, a rotor should be a perfectly flat surface. The brake shops will use a lathe to true the surface if the rotor has just normal wear. Only so much thickness of the rotor can be removed. If the rotors have been scored from the brake pads wearing down to the pad's metal backing (metal-metal contact), then it is most likely too deep to resurface.