Shimano Ultegra Di2 ST-R8170 / BR-R8170 (12Speed)

Wireless Command. Hydraulic Mastery.

This pre-bled, high-performance Shimano Ultegra Di2 Kit pairs the advanced wireless ST-R8170 Dual Control Levers with the ultra-stiff BR-R8170 Hydraulic Disc Brake Calipers. By leveraging a secure, ultra-low-power proprietary wireless signal, the levers send instantaneous commands to your derailleurs. This achieves an incredibly clean, clutter-free front cockpit profile while preserving a massive 1.5 to 2-year battery lifespan off a pair of easily replaceable CR1632 coin cells inside the hoods.

Why the Ultegra R8170 Shift & Brake System is the Rider's Choice:

• Pro-Refined Hood Ergonomics: The completely redesigned hoods feature an elevated peak and a longer, subtly curved profile. This provides an exceptionally secure hand position when riding on the hoods, allowing you to easily lock your forearms flat in a wind-cheating aerodynamic tuck.

• SERVO WAVE Brake Modulation: Imported directly from Shimano’s elite mountain bike brakes, SERVO WAVE technology redesigns the lever stroke. The brake pads travel quickly to make initial contact with the rotor, then optimize the leverage ratio to provide massive, progressive stopping modulation with incredibly light finger effort.

• 10% Wider Pad Clearance: The compact, mono-body BR-R8170 calipers are engineered with an extra 10% of physical space between the pads and the rotor. This virtually eliminates annoying, metallic pad rub when you are throwing down massive watts out of the saddle or grinding up long climbs.

• Enhanced Multi-Button Distinction: Designed with an increased height offset between the primary up-shift and down-shift buttons on the lever blade, making it effortless to click the correct gear even when wearing thick winter gloves or sprinting at maximum heart rate.

• Seamless Customization Core: Features an integrated third remote button on top of each hood peak. Using the Shimano E-TUBE smartphone app, you can customize these to scroll pages on your Garmin Edge 540, trigger specialized multi-shifts, or cycle front chainrings.

• One-Way Bleeding Architecture: The one-piece rigid caliper architecture streamlines garage maintenance, utilizing an optimized fluid path that makes flushing and bleeding the system completely hassle-free.

Technical Specifications:

• Series Tier: Ultegra R8100 Series

• Speed Profile: 2x12Speed Electronic Di2

• Shifter Connectivity: Wireless (or optional wired configuration using EW-SD300 wires)

• Brake Caliper Type: Flat Mount Hydraulic Disc

• Hydraulic Fluid: Shimano Mineral Oil

• Shifter Battery Source: 1x CR1632 per lever (1.5-2 year lifespan)

• Adjustment Range: Independent Tool-Based Reach Adjust & Free Stroke Adjust

• Hose Standard: SM-BH90-JK-SSR High-Pressure Hose

• Average Weight: ~391 grams (per pair of shifters) | ~146 grams (per caliper)

The Alegro Perspective: The Ultegra R8170 system is our automatic benchmark recommendation. In past generations, choosing Ultegra meant accepting a slight performance drop compared to Dura-Ace. With this 12-speed platform, that gap has completely vanished. The shifting speed, the wireless protocol, and the brilliant SERVO WAVE braking mechanics are totally identical to the pro tier. Ultegra simply substitutes aluminum lever blades for carbon ones to save you hundreds of dollars. The 10% wider pad clearance is a complete game-changer, giving you a completely silent ride even through wet grime and gritty downpours.

Wireless Precision Command. Infinite Deceleration Confidence. Elevate Your Controls with Shimano.