The Shimano 105 ST-R7120 is a 12-speed dual control lever pairing hydraulic disc braking with mechanical shifting in a single, ergonomically refined unit. Bundled with the BR-R7170 flat mount front brake calliper, this right-hand lever brings 105-level performance to road and endurance riders who want confident, consistent braking with light, precise shifting action.

Highlights

• Ergonomic lever design: Revised bracket shape and blade geometry developed from broad hand-shape data, creating a shorter lever access curve for riders across a wide range of hand sizes.
• Hydraulic disc confidence: Shimano mineral oil hydraulic system delivers powerful, modulated braking with consistent feel in all conditions.
• Auto pad-clearance adjustment: The hydraulic reservoir automatically compensates for pad wear, maintaining optimal rotor clearance over the life of the pads.
• OptiSlick inner cable: Factory-coated shift cable reduces friction for crisp, light mechanical shifting across 12 speeds.
• Reach adjustment: Lever reach is adjustable via a 2.5 mm hex key — up to 13.3 mm of adjustment for a personalised fit.
• BR-R7170 flat mount calliper included: Compact, light two-piston calliper with 10% wider pad clearance to reduce rotor rub, and one-way bleeding for easy maintenance.

Mechanical Shifting, Hydraulic Braking

The ST-R7120 combines 12-speed mechanical gear actuation with hydraulic brake control — a practical pairing for riders who prefer cable-actuated drivetrains without sacrificing the braking performance of hydraulics. OptiSlick-coated inner cables and low-friction OT-SP41 (lever side) and OT-RS900 (derailleur side) outer casings keep shifts light and precise over thousands of kilometres.

Ergonomics & Control

The redesigned bracket shape fits naturally in the hand, with a wing-like blade profile that reduces the reach distance to the lever. Whether riding on the hoods or in the drops, control is immediate and accessible. Reach can be fine-tuned on the bike with a 2.5 mm hex key, making fit adjustments straightforward without needing to remove bar tape.

Compatibility & Fit

Right-hand lever for 12-speed rear shifting. Fits road handlebars with a 23.8–24.2 mm clamp diameter. Hydraulic system uses Shimano mineral oil only — do not use DOT fluid. The included BR-R7170 calliper is flat mount and pairs with Shimano 105 R7100 rotors (sold separately). Compatible cassettes include CS-R7101-12 and CS-HG710-12; compatible chains include CN-M7100, CN-M8100, and CN-M9100. Brake hose kits SM-BH90-JK-SSR or SM-BH90-J-SSR required (sold separately).