Race-ready hydraulic disc braking and Di2 electronic shifting in a single, seamlessly integrated left-hand lever. The Shimano Dura-Ace ST-R9170 pairs flagship ergonomics and carbon composite construction with the razor-sharp stopping power of the BR-R9170 rear flat-mount caliper — arriving pre-matched and bled, ready to build around.

Highlights

• Dura-Ace Di2 11-speed hydraulic dual control lever (left hand, front derailleur)
• Integrated fluid reservoir with automatic pad-wear compensation
• BR-R9170 rear flat-mount hydraulic disc brake caliper included
• Carbon composite hood and lever body for minimal weight
• Reach adjust and free-stroke adjustment for every hand size
• Hidden button on top of hood for additional Di2 function mapping
• Three switches per lever; two e-Tube SD50 ports
• Shimano mineral oil hydraulic system — clean, consistent feel
• Compatible with 10 or 11-speed Dura-Ace Di2 drivetrains
• Not compatible with SW-R610 sprint shifters

Lever & Shifting

The ST-R9170-L is engineered alongside the rest of the Dura-Ace R9150 Di2 groupset for a cockpit that does more with less. The carbon composite hood profile matches a traditional rim-brake lever in feel, while the enlarged Di2 shift buttons deliver a positive click and can be fully remapped using Shimano's E-TUBE Project software. A concealed button on top of the hood adds an extra programmable function — ideal for multi-shift or satellite mode. Two SD50 e-Tube ports allow clean cable routing to front derailleur and junction box.

Hydraulic Braking

The integrated hydraulic reservoir automatically compensates for brake pad wear, maintaining a consistent lever feel throughout pad life. The BR-R9170 rear caliper uses a flat-mount standard — the lowest-profile, stiffest mounting system available for road disc — and ships with resin pads. Bleeding is a one-way process for a clean, easy service. ICE TECHNOLOGIES FREEZA heat management keeps braking performance stable under sustained descents. Rotor compatibility is 140 mm direct or 160 mm with a flat-to-flat adapter (sold separately).

Compatibility & Fit

Designed for Shimano Dura-Ace R9150 Di2 systems and compatible with 10 or 11-speed Di2 road drivetrains. Requires a flat-mount disc frame and SM-BH90 hydraulic hose (sold separately unless pre-built). Di2 wiring and junction box are not included. This lever does not feature a dedicated sprint shifter port — the SW-R610 is not compatible. Use SW-R9150 satellite shifters if sprint-bar control is required.