The Shimano RT-CL900 is the Dura-Ace level disc rotor, built to shed heat fast and run quietly on long, steep descents. Its three-layer Ice Technologies Freeza construction keeps braking consistent when the pace and the gradient pick up, while a reinforced arm design cuts the pinging and ticking you can get from cheaper rotors.

Highlights

• Top-tier Dura-Ace braking performance with consistent power on long descents
• Ice Technologies Freeza cooling keeps the rotor and pads working under heat
• Reinforced arm shape runs quieter than previous Dura-Ace rotors
• Centre Lock fitment for fast, tool-light wheel swaps
• Works with both resin and metal pad compounds
• Lockring included in the box

Heat management that holds up

Ice Technologies sandwiches an aluminium core between two stainless-steel braking surfaces, and the Freeza fins draw heat out and away from the pad contact area. The result is steadier braking and less fade when you are hard on the brakes for a sustained descent.

Quieter braking

The arm shape that connects the braking track to the Centre Lock carrier is more robust than earlier designs, reducing the flex that causes brake noise so the rotor stays quieter under load.

Compatibility & fit

This is a 160mm Centre Lock rotor. It uses an internal-serration lockring (supplied), so it is fitted and removed with a cassette/Centre Lock lockring tool rather than an external-spline tool. It mounts to any Centre Lock hub and is compatible with Shimano resin and metal disc brake pads. Sold individually (one rotor).