Shims be gone! One of the longest running, more petty battles in component standards is being resolved. Shimano (and others) have long maintained a 203mm diameter disc brake rotor. SRAM (and others) liked the round numbers of a 200mm rotor. Shimano’s 203mm was a nice round number, eight inches, before disc rotors moved to metric sizing.
Now, Shimano is making its disc rotors 200mm. A tiny change that does away with an annoying standard discrepancy. It was one of the easier ones to fix, as you only needed tiny washers to make a caliper designed for 200mm rotors work with a 203mm rotor. But still, progress is progress. Let’s celebrate.
Thicker rotors debut new-to-Shimano diameter
The bigger change to Shimano’s rotor is their thickness. Rotors beef up from 1.75mm to a full 2.2mm thickness. Why? To significantly improve durability for more aggressive riding and for eMTB use. The thicker rotors are supposed to give more control, as there’s less temperature variation. They’ll also be more durable and more impact-resistant since they are beefier.
This change applies to the 200mm and 220mm version of the Centerlock (RT-CL750) and six-bolt version of Shimano’s CL750 rotor. It is compatible with all current generation four-piston brake calipers, from Deore to XTR.