IS 6 holes
Traditional mounting system using six bolts to attach
the disc to the hub. Its advantage is the wide selection of discs from different
manufacturers and bolt mounting, usually with a T25 Torx head. The bolts are
available in various colors, including lightweight titanium. A minor advantage
of this system is that the hub end caps can be removed easily, without
dismantling the disc, so the area around the bearing can be dried or cleaned
after a rainy or muddy race.
CenterLock
Spline mounting system. The hubs are lighter, but
paradoxically, because the discs are heavier, the complete system weighs roughly
the same as the IS 6-hole version. Removing the discs is easier and
significantly faster. There are two types of lockrings: with internal or
external splines. Internal splines are used with 12 mm axles and removed with a
cassette tool. Lockrings with external splines are used with 15 mm axles and
installed using a tool for Hollowtech bottom brackets.