I need to know how to tell difference in disc brake mounts on my mountian bike. I am changing to a 8" rotor?

Question

I need to know how to tell difference in disc brake mounts on my mountian bike. I am changing to a 8" rotor?

Answer 1

Unless you are downhilling 8" rotors are a waste of money. Nobody needs that type of power for XC or all-mountain.

Answer 2

Its not always the mounts which are vital. you'll obviously need the correct mounts for the calliper.

the calliper needs to match the size of the rotor.

IS mounts are holes perpendicular to your wheels.

Post mounts are like holes drilled in you fork lowers.

Answer 3

Well, unless you have a disc-equipped bike from the 1990's, you won't really have to do anything except buy 1 or 2 8" rotors and their accompanying calipers and hubs. It would also be wise to check and make sure your fork and seatstay will be able to handle the increased stress loads which a larger 8" rotor will produce, otherwise they can crack and fracture when riding. If you have a disc-equipped bike from the 1990's, you may need to get a more modern hub, because modern disc brakes have 6 bolts that attach the rotor to the hub. 1990's bikes can have any number of bolts, not just six. If, by chance, your 1990's bike does have 6 bolts, then all you have to do is read the above instructions. Otherwise, get a more modern hub. I hope this helps.