Before choosing a disc brake, you must work out what mounting system you will require to work with your front forks. Most forks are fitted with International Standard mounts but all Manitou forks use their own system. Some brake calipers fit directly onto a Manitou system whereas others require an adapter. All rear mounts are International Standard. Most disc rotors fit to the wheel with a six-bolt International Standard pattern so make sure your hubs have the required bolt holes. Shimano have started a new system called CenterLock which is not compatible and requires specific hubs.