The Shimano RT-MT905 is the top-tier 6-bolt rotor in Shimano's mountain bike range, bringing ICE TECHNOLOGIES FREEZA cooling to traditional 6-bolt hubs. It runs cooler on long, hard descents, which means more consistent braking, less fade and quieter performance when you need it most.

Highlights

• Three-layer stainless-aluminium-stainless construction pulls heat out of the braking surface fast
• Exposed aluminium radiator fin (FREEZA) sheds heat for cooler running than a standard Ice Tech rotor
• Around 150°C cooler than a conventional stainless steel rotor under hard use, for less brake fade
• Standard 6-bolt ISO mounting fits the vast majority of MTB and gravel hubs
• Cooler operation means more consistent modulation, more power and longer pad life

FREEZA cooling, on a 6-bolt rotor

FREEZA rotors use a thin layer of aluminium sandwiched between two stainless steel braking surfaces, with the aluminium core extended into an exposed radiator fin. That fin acts like a heatsink, drawing heat away from the brake track so the rotor stays cooler on sustained descents. The RT-MT905 brings this technology to the 6-bolt standard, so riders running 6-bolt hubs no longer have to choose Center Lock to get FREEZA cooling.

Why cooler is better

Heat is the enemy of consistent braking. As a rotor heats up, power can fade and the lever feel changes. By running roughly 150°C cooler than a standard stainless rotor in extreme conditions, the RT-MT905 helps keep braking power and modulation predictable, reduces noise, and extends the life of your brake pads.

Compatibility & fit

This is the 180mm version with a 6-bolt ISO mounting interface, fitting any standard 6-bolt disc hub. It pairs with Shimano hydraulic disc brake calipers, including XTR and Saint, and is cross-compatible with other Shimano MTB brake systems. New rotor thickness is 1.8mm with a Shimano minimum wear limit of 1.5mm. Sold as a single rotor; rotor bolts are not included.