The Shimano Dura-Ace BR-R9100 is the front rim brake calliper from Shimano's flagship R9100 road groupset. Built for competitive road cyclists who demand the highest levels of stopping power, modulation, and light weight, it brings measurable gains in braking stiffness and tyre clearance over its predecessor — without adding weight.

Highlights

• SLR-EV dual-pivot design: Short-arm symmetric pivot geometry with twin bearings and a roller delivers a more linear braking curve, superior modulation, and consistent power from the first squeeze to the last.
• 40% stiffer brake arch: Torsional stiffness is improved by more than 40% versus the previous generation, translating braking input directly into stopping force with minimal flex.
• Titanium pivot hardware: Hinge pins and cable anchor bolt are machined from titanium — shaving weight where it matters without compromising durability.
• Magnesium brake shoe holders: Angle-adjustable cartridge-style holders allow precise toe-in setup and accept both R55C4 (aluminium rim) and R55C4 carbon compound shoes.
• Wider tyre clearance: Accommodates tyres up to 700×28c, giving riders running endurance or all-round setups genuine rim brake compatibility.
• Spring tension adjustment: Onboard spring tension adjuster lets you dial in pad retraction precisely without tools.

Construction & Materials

The BR-R9100 calliper arms are forged aluminium with an anodised finish for long-term corrosion resistance. The centre bolt is titanium, and the pivot assembly uses thrust bearings and coated bushings between the arms for a smooth, consistent feel across the brake's full range of travel. The result is a calliper that feels responsive and linear whether you're feathering the brakes into a technical descent or scrubbing speed before a sprint.

Compatibility & Fit

This is the front calliper in the BR-R9100 range, with a CS-49 (49 mm) reach and 10.5 mm sunken nut mounting. It is compatible with standard dual-pivot brake bosses on road frames. Rim width compatibility: 20.8–28 mm. Maximum tyre size: 700×28c. Supplied with R55C4 brake shoe set (suitable for aluminium rims); R55C4 carbon compound shoes are available separately for carbon rim compatibility. Works with all Shimano Dura-Ace R9100 series brake levers (including ST-R9100 dual-control levers) and any standard drop-bar lever with a compatible cable pull.