The Shimano BR-RS811-R Rear Direct Mount Brake Caliper delivers powerful, controlled road braking in a sleek, low-profile design engineered for under-bottom-bracket mounting. Designed around Shimano’s SLR-EV braking system, it provides an excellent balance of rigidity, low weight, and dependable stopping power.
The direct-mount configuration integrates the brake closely with compatible road frames, creating a clean installation while supporting precise and responsive braking. The BR-RS811-R features a 51mm reach and accommodates tires up to 28C with compatible rim widths from 20.8mm to 28mm.
Shimano equips the caliper with R55C4 cartridge brake shoes for dependable braking performance on compatible aluminum braking surfaces. The cartridge shoe holder allows convenient pad replacement, while adjustable shoe angle and spring tension make it possible to fine-tune brake setup and performance.
The BR-RS811-R also incorporates tire guide bumpers and is compatible with Shimano’s SLR-EV system. For cable adjustment and quick-release functionality, Shimano specifies use of an SM-CB90 inline cable adjuster.
- Rear direct-mount road brake caliper
- Designed for under-bottom-bracket mounting
- Low-profile integrated caliper design
- SLR-EV compatible
- 51mm brake reach
- Maximum tire size: 28C
- Compatible rim width: 20.8–28mm
- R55C4 cartridge brake shoes
- Cartridge-style brake shoe holder
- Adjustable brake shoe angle
- Adjustable spring tension
- Integrated tire guide bumpers
- SM-CB90 inline cable adjuster required for cable adjustment and quick-release functionality
Model: BR-RS811-R
Position: Rear
Mount: Direct Mount / Under Bottom Bracket
Reach: 51mm
Brake Shoe: R55C4
Maximum Tire Size: 28C
Compatibility: Shimano SLR-EV
