Shimano Ultegra DI2 Disc 12v Right-Hand Lever ST-R8170R - ISTR8170RF

The ST-R8170-RShimano (part no. ISTR8170RF) is a right-hand 12-speed Di2 electronic brake and shifter lever, designed for road bikes fitted with hydraulic disc brakes. It forms part of the Ultegra R8100 range, just below Dura-Ace, and incorporates many of the top-of-the-range technologies Shimano, to offer more precise, comfortable and faster control.

This right-hand shifter controls the hydraulic rear brake and the Di2 electronic rear derailleur, featuring a completely redesigned ergonomic design and semi-wireless connectivity (wireless buttons + centralised Di2 system).

Technical specifications

• Brand: Shimano
• Range: Ultegra R8100
• Model: ST-R8170-R
• Part number: ISTR8170RF
• Gears: 12-speed
• Type: dual-control lever (brake + gear shift)
• Drivetrain: Shimano Di2 electronic
• Brakes: hydraulic disc
• Compatibility: Shimano Di2 12-speed road groupsets (Ultegra / Dura-Ace / 105 depending on configuration)
• Adjustments: reach adjust + free stroke adjust
• Weight: approx. 391 g per pair (groupset reference)

Key features

• Ultra-fast and precise Di2 gear changes
• Powerful and very progressive hydraulic braking (SERVO WAVE)
• Modernised ergonomics for greater comfort on long rides
• Semi-wireless system for a cleaner cockpit
• Fine-tuning options (reach and lever free travel)
• Shimano ’s reliability in intensive road and endurance use

FAQ

What is the ST-R8170-R right-hand grip used for?

It controls the hydraulic rear brake and the electronic rear derailleur on a Shimano Di2 12-speed road bike.

Is it compatible with 11-speed systems?

No, it is designed exclusively for Shimano Di2 12-speed drivetrains (R8100 / R9200).

Is it a wireless controller?

Partially: the buttons communicate wirelessly with the Di2 system, but the whole bike is still controlled by a central electronic network.

Can it be used without disc brakes?

No, this model is only compatible with hydraulic disc brakes.

How does it differ from mechanical Ultegra?

Di2 offers electronic gear changes that are faster, smoother and require much less effort.