The Shimano Dura-Ace BR-R9110-RS is the seat stay direct mount rear rim brake calliper from the R9100 groupset — Shimano's flagship road component line. Designed for frames with integrated direct mount bosses, it delivers a significant aerodynamic and stiffness advantage over traditional single-bolt calipers, making it the choice for riders chasing marginal gains on race-day bikes.

Highlights

• Direct mount seat stay fitment: Two-bolt attachment to the frame's dedicated bosses eliminates flex for more precise, confident braking.
• SLR-EV dual symmetric pivot: Twin bearings and a roller minimise friction and deliver superior modulation with a linear, predictable braking curve.
• 43% stiffer than previous Dura-Ace: Reshaped aluminium caliper arms transmit cable force directly into stopping power with minimal flex.
• 28mm tyre clearance: Generous clearance accommodates wider road tyres for comfort and versatility without sacrificing aerodynamics.
• R55C4 brake pads included: Shimano's highest-performance rim pads provide excellent all-weather braking on aluminium braking surfaces.
• Near-black high-polish finish: Subtle dark finish suits modern aero frameset aesthetics while keeping weight to just 145g.
• Aerodynamic quick-release lever: Reshaped inline QR lever is more streamlined than previous generations and simple to operate.

Technology

The BR-R9110-RS uses Shimano's SLR-EV (Super Linear Response – Enhanced Version) pivot mechanism, which pairs twin pivot bearings with a contact roller to virtually eliminate pivot friction. The result is a more linear cable pull, cleaner modulation throughout the braking zone, and a consistent feel regardless of conditions. The caliper body itself has been extensively reworked for the R9100 generation, with reshaped arms that are substantially stiffer than the 9000 series while maintaining a lightweight profile.

Design & Finish

The near-black finish with high-polish detail was developed specifically for the R9100 series to complement modern aero framesets. The adjustable pad holders accept R55C4 cartridge pads and can be angled and pivoted to achieve optimal pad-to-rim contact alignment — critical for consistent braking and even pad wear.

Compatibility & Fit

Designed for frames equipped with seat stay direct mount bosses (ISO direct mount standard). Compatible with all Shimano 11-speed STI road levers, including the 9100, 9150, 9000, 6800, and 5800 series — the cable pull ratio is unchanged across generations. Suitable for aluminium braking surfaces; external rim width range 20.8–28mm; standard 51mm reach. Supplied with Shimano R55C4 brake pads.