The Shimano Ultegra ST-R8170 right lever paired with the BR-R8170 front hydraulic disc brake caliper delivers race-proven braking performance and wireless Di2 electronic shifting in one refined package — ideal for riders building or upgrading to a full Ultegra R8100 Di2 disc groupset. In the Australian setup, the right lever controls the front brake.

Highlights

• Ultegra R8100 Di2 platform: 12-speed wireless electronic shifting eliminates cockpit cables for a cleaner, more aerodynamic setup.
• Servowave braking: Progressive lever feel that brings pads to rotor contact quickly, then multiplies power sharply — excellent modulation across the full stroke.
• Hydraulic confidence: Shimano mineral oil hydraulic actuation delivers consistent, fade-resistant braking in all conditions.
• BR-R8170 flat mount caliper: Redesigned two-piston caliper with increased pad clearance for quieter operation and improved initial braking response.
• L03A Resin Ice-Tech pads: Finned resin pads with Ice-Tech heat-management for sustained braking performance on long descents.
• One-Way Bleeding: Separated bleed nipple and opening screw streamline fluid maintenance and reduce air ingestion risk.
• Easy Hose Joint System (J-Kit): Simplifies hose installation and replacement without specialist tools.
• Reach adjust: Fine-tune lever position across a wide range to suit any hand size or riding style.
• Long-life Di2 battery: CR1632 coin cell powers wireless shifting electronics with an estimated 1.5–2 year service life.

Wireless Di2 Electronic Shifting

The ST-R8170 integrates Shimano's latest wireless Di2 platform, removing shift cables from the cockpit entirely. Gear changes are delivered via electronic signal — fast, precise, and repeatable under any load or condition. The lever body is constructed from carbon fibre reinforced polymer (CFRP) for a light, rigid feel, with an aluminium brake blade for durability. The lever also supports wired Di2 configuration via EW-SD300 cables if required by the build.

Servowave Hydraulic Braking

Servowave technology gives the ST-R8170 its distinctive feel: initial lever travel brings the pads to the rotor quickly with minimal effort, then mechanical advantage increases sharply as braking force is applied. The result is superb modulation — precise speed scrubbing in the initial stroke, with maximum stopping power available when needed. The BR-R8170 caliper has been redesigned with a mono-body construction that increases pad clearance, reducing contamination noise while maintaining exceptional power and feedback.

Maintenance & Serviceability

The BR-R8170 uses Shimano's One-Way Bleeding system, which separates the bleed nipple from the opening screw for a cleaner, more reliable fluid maintenance process. The Easy Hose Joint System (J-Kit) makes brake hose installation and replacement straightforward. The L03A Resin Ice-Tech pads are a readily available consumable; the caliper is also compatible with K03S resin and 04C metal pads.

Compatibility & Fit

Designed for Shimano Ultegra R8100 Di2 12-speed groupsets. The BR-R8170 caliper uses flat mount fixing and is supplied configured for front wheel use. Compatible with Shimano mineral oil only — do not use DOT fluid. Pairs with SM-BH90 series brake hose (included via J-Kit). Compatible with 140mm or 160mm rotors; Shimano recommends RT-MT800 series rotors for full Ice-Tech heat-management benefits. In the Australian setup, the right-hand lever controls the front brake.