The Shimano 105 ST-R7120-L with BR-R7170 brings hydraulic disc braking power and precise 2x12-speed mechanical shifting into a single, ergonomically refined package. Designed for road cyclists who want dependable, high-performance stopping alongside the tactile feedback of mechanical shifting — without compromise.

Highlights

• Hydraulic disc braking: Consistent, powerful braking with minimal hand effort, even in wet conditions.
• Mechanical 12-speed shifting: Familiar, direct cable-pull shifting compatible with Shimano 105 R7100 drivetrains.
• Updated ergonomic lever shape: Revised lever position and bracket form developed from extensive hand-shape data, creating a shorter lever access curve for a wider range of rider hand sizes.
• Reach adjust: Fine-tune lever distance from the bar to suit your grip and comfort preference.
• Flat mount caliper: BR-R7170 flat mount design is lightweight and compact, keeping the caliper tight to the frame for a clean, aerodynamic profile.
• Wider pad clearance: 10% wider pad spacing compared to previous-generation calipers reduces the chance of rotor rub during normal riding.
• One-way bleeding: Simplified brake bleed procedure keeps maintenance quick and clean.
• Easy Hose Joint System: Facilitates brake hose replacement without full brake system disassembly.

Lever & Caliper Detail

The ST-R7120-L dual control lever uses Shimano's proven combined shift-and-brake design, combining OPTISLICK inner cable shifting with hydraulic brake actuation via mineral oil. The lever bracket has been reshaped to sit more naturally in the hand, both on the tops and in the drops, and reach adjustment is built in for a precise fit.

The BR-R7170 caliper features a two-piston design with flat mount attachment and is compatible with resin (K05S-RX) or metal (L04C-MF) pad compounds. Mineral oil hydraulic fluid provides a stable feel across a wide temperature range and is non-corrosive to painted surfaces.

Compatibility & Fit

This set is the left-hand lever with rear brake caliper, supplied with a 1700mm brake hose (SM-BH90-J-SSR or SM-BH90-JK-SSR) suited to rear routing. Compatible with Shimano 105 R7100 2x12-speed drivetrains. Brake caliper uses flat mount standard. Compatible rotors: SM-RT70, SM-RT64 (rotor not included). Clamp diameter: 23.8–24.2mm. Brake fluid: Shimano Mineral Oil. Note: in Australian fitment convention, the left lever controls the rear brake.