Bring Dura-Ace Di2 precision and hydraulic disc braking confidence to your time trial or triathlon cockpit. The ST-R9180-L is the left-hand lever of Shimano's Dura-Ace R9150 Di2 TT/Tri system, pairing electronic front shifting with powerful hydraulic braking in a single, clean-routing unit designed specifically for aero bar ends.

Highlights

• Dura-Ace R9150 Di2 series — top-tier electronic shifting performance
• Integrated hydraulic disc brake control with reach adjustment
• Left-hand lever: 2-speed front derailleur shifting
• Single customisable button per lever for Synchro Shift compatibility
• Ultra-lightweight at 99g per lever
• Clamp band suits aero bar ends: 19.0–22.5mm inner diameter
• SD50 Di2 port for E-Tube wired connectivity
• Shimano mineral oil hydraulic system for consistent, fade-resistant braking

Di2 Electronic Shifting

The ST-R9180-L integrates directly with Shimano's E-Tube Di2 wiring system, connecting to the BT-DN300 battery via a wired SD50 port. A single programmable button controls front shifting, and with Synchro Shift enabled, the system can coordinate front and rear derailleurs automatically for seamless gear transitions — ideal for the repeated position changes of triathlon and time trial racing.

Hydraulic Disc Braking

The lever's hydraulic actuation delivers powerful, modulated stopping force with minimal hand effort — critical when riding in an aerodynamic tuck. Brake lever reach is adjustable to suit different hand sizes and riding styles. The system runs on Shimano mineral oil and is designed to work with the BR-R9170 front calliper. The SM-BH90-JK-SS straight-joint hose kit simplifies routing through aero bar ends.

Compatibility & Fit

Compatible with Shimano Dura-Ace R9150 Di2 groupsets. Firmware version 3.3.0 or later (via E-Tube Project) extends compatibility to Dura-Ace R9200 and Ultegra R8100 series components. Clamp inner diameter 19.0–22.5mm fits standard TT/Tri bar end profiles. Recommended brake caliper: BR-R9170. This listing is for the left-hand lever only; the right-hand lever (11-speed rear shifting) is sold separately.