Originally Posted by
jrickards
Understood but both of these are for disc brakes yet only the left one has the recognizable six bolt attachment for the rotor.
And when you pop the rubber cover off the left side of the Alfine hub, voila! Centerlock rotor mount.
There are two "standards"--ISO six-bolt and Shimano Centerlock. Centerlock rotors mount with a lock ring identical to Shimano cassettes, and it uses the same cassette tool.