DURA-ACE ST-R9170 DI2 HYDRAULIC LEVER SET
Shimano’s Di2 11 speed drivetrain with E-Tube technology offers customizable shifting set-up so no matter your cycling discipline, you are fully in control in how you program your shifting. Sold as individual right and left levers, the levers include specific BR-R9170 flat mount brake calipers and hydraulic hose kits.
Shimano’s Di2 shifting is the gold-standard in which all other shifting is compared. Mating superior all-weather braking power and modulation with the industry’s best shifting creates the most desirable components for your drop bar bike.
The ergonomics of the 9170 hydraulic lever are nothing short of phenomenal. Shimano made the clicks more positive, which provides great feedback when operating the levers in freezing conditions with thick gloves, during a muddy ‘cross race, or over washboard gravel roads. The ability to integrate satellite buttons for climber and sprinter shifters carries over from previous versions, but the new textured hoods provide excellent cushion and grip when you’re shifting at the levers.
By designing flat mount brakes, Shimano was able to drop weight while increasing power and offering even more of the highly vaulted modulation. The caliper is very low-profile and the finish matches the rest of the Dura-Ace group. One of our favorite things about Shimano brakes is that they use mineral oil, which is safer for the environment and won’t harm your frame’s finish.
Though its proprietary mineral oil is more heat-resistant than standard DOT options, Shimano still worked hard to keep operating temperatures low. No one wants to carry around large heavy rotors on the road, so the brand looked at design and the materials used on the rotors, pads, and pistons to keep temps in check. The resin pads are super quiet and offer Dura-Ace-grade modulation, and the aluminum fins dissipate heat quickly and allow you to run smaller diameter rotors without the fear of overheating or fading on long descents. Ceramic pistons act as a heat sink to shield the caliper and fluid from the heat generated by the pads, and an aluminum core draws the heat away from the face of the stainless steel rotor.
Flat mounts are the standard on newer ‘cross, road, and gravel framesets. In the wind tunnel, flat mounts have less of an impact on aerodynamic performance versus post mount, so if you’re fretting about drag as a deciding factor, worry no more. Rotors are sold separately and the Shimano center lock versions in 140 or 160mm are highly recommended.
The new E-tube Di2 system allows for a completely custom shifting setup. To take advantage of this system you will need to use a BM-DN100 or BT-DN110 battery and the EW-WU101 ANT/BLE wireless connector to connect to your tablet or phone. Each shift lever is programmable to operate either derailleur and you can choose if you want that button to upshift or downshift. Shimano also adds SyncroShift which helps to manage sequential shifting with two options. In fully synchronized mode, the front derailleur will automatically shift up or down based on the position of the rear derailleur and the set ratios you determine in the app. In semi-syncronization mode, you will still shift front and rear derailleurs normally but after a front shift is initiated, the rear derailleur will upshift or downshift depending on the direction of the front shift to keep cadence optimal and allow you to focus on pedaling and not gear ratios.
- A pro-level road lever and disc brake caliper
- New ergonomics keep the hood size similar to non-hydro shifters
- Refined lever shapes with more positive shift response
- Free-stroke adjustment for lever and pad contact placement
- E-Tube allows for SyncroShift modes and button customization
- Mineral oil is safer and more resistant to high temperatures
- Rotors are not included
|Lever||Shimano Dura-Ace Di2 ST-R9170, 2×11 speed|
|Lever Adjustability||reach, free-stroke|
|Caliper||Shimano Dura-Ace BR-R9170|
|Rotor Size||[recommended] 140 – 160mm|
|Manufacturer Warranty||3 years|