The Shimano GRX ST-RX810-LA is a left-hand hydraulic disc brake lever purpose-built for gravel riders who want dropper post capability without adding a separate remote. It integrates brake control and seatpost cable actuation in a single lever body, keeping your cockpit clean and your hands on the bars when the terrain demands it. Designed for 1x11-speed GRX gravel groupsets.

Highlights

• Integrated dropper remote: Built-in cable actuation for dropper seatposts delivers up to 8.3mm of cable stroke, compatible with most third-party dropper posts that use a cable at the post end.
• SERVOWAVE brake lever: Shimano's SERVOWAVE mechanism moves the brake pads into contact quickly with minimal lever travel, then increases power as you squeeze — sharp initial response, strong stopping force.
• Reach adjust: Tool-free lever reach adjustment lets you dial in the distance from bar to brake lever to suit your hand size and riding style.
• Free stroke adjustment: Fine-tune the point at which the brake engages to match your preferred feel and pad clearance.
• Anti-slip lever surface: Ribbed grip texture on the brake lever blade keeps your finger secure in wet and muddy conditions.
• Mineral oil hydraulics: Uses Shimano mineral oil for consistent, fade-resistant braking feel and easy maintenance.
• 1x11 optimised: Designed for single-chainring gravel drivetrains — the lateral lever movement unused by a front derailleur activates the dropper post instead.

GRX Gravel Integration

The ST-RX810-LA is part of Shimano's flagship GRX 11-speed gravel groupset, engineered specifically for off-road and mixed-surface riding. The lever's ergonomic hood shape suits drop-bar riding in all positions, and the raised brake lever axis (18mm higher than road equivalents) provides strong braking leverage from the hoods — where gravel riders spend most of their time.

Dropper Post Compatibility

The integrated remote operates dropper posts via a standard Bowden cable with 8.3mm maximum cable stroke. It is compatible with most third-party dropper seatposts that clamp at the post end. Dropper posts with lever-end cable clamping may require an adapter. Shimano recommends pairing the ST-RX810-LA with a compatible dropper post (not included) and the BR-RX810 hydraulic disc brake calliper for best results.

Compatibility & Fit

Left-hand lever for use with 1x11-speed GRX gravel groupsets. Compatible with standard 23.8–24.2mm drop-bar clamp diameter. Brake system uses Shimano mineral oil (not DOT fluid). Recommended calliper: BR-RX810. Hydraulic hose: SM-BH90 series. Sold without hose, calliper, or mineral oil — these must be purchased separately or installed by a mechanic.