The Shimano 105 ST-R7120 is the left-hand dual control lever from Shimano's R7100 series, combining 2-speed mechanical front-derailleur shifting with the confident stopping power of hydraulic disc brakes. It's the ideal upgrade for road cyclists who want the reliability and feel of 105 performance without reaching into Ultegra territory.

Highlights

• Redesigned lever blade: A shorter lever access curve means riders of all hand sizes can reach the brake lever with ease, whether on the hoods or in the drops.
• Reach adjustment: 13.3 mm of reach adjustment via a 2.5 mm hex key lets you dial in the perfect lever position for your hand shape and riding style.
• Hydraulic disc braking: Shimano mineral oil hydraulic actuation delivers consistent, modulated braking in all conditions with automatic pad-to-rotor clearance compensation.
• Mechanical 2-speed shifting: Controls a front derailleur with crisp, mechanical cable actuation — compatible with FD-R7100 and FD-RX820.
• Optislick inner cable: The included Optislick-coated shift cable reduces friction and extends service intervals for smooth, reliable front shifts.
• Easy bleeding: M7 funnel port allows straightforward mineral oil bleeds at home or in the workshop.

Ergonomics & Design

The R7120 lever body is constructed from composite material with an aluminium brake lever blade, keeping weight in check while providing the stiffness needed for precise hydraulic actuation. The bracket shape has been refined using hand-shape data from a broad range of riders, so it sits naturally in the hand whether you're sprinting or descending.

Compatibility & Fit

This is the left-hand lever controlling 2-speed front shifting. It fits standard drop handlebars with a clamp diameter of 23.8–24.2 mm. Recommended brake caliper is the BR-R7170; brake hose (SM-BH90-JK-SSR or SM-BH90-J-SSR) is sold separately. Compatible front derailleurs: FD-R7100, FD-RX820. For 12-speed rear shifting, the matching right-hand lever is ST-R7120-R. Uses Shimano mineral oil only — do not use DOT fluid.