Ultegra Di2 ST-R8070 Shifter & Disc Brake Caliper
Many may argue whether or not you really need electronic shifting and hydraulic disc brakes on road bikes, but after riding bikes equipped with the newfangled technology, we'd have a hard time going back to shifting and braking systems that rely on cable tension and slack to achieve its actuation. Digital shifting and hydraulic braking are so much more precise, powerful, and perhaps even more importantly, it's reliable and doesn't require constant adjustments. Take those components and build them up under the Ultegra moniker and it screams value and performance, really only giving up a slight weight penalty to Dura-Ace through the use of less exotic materials. Indeed, Ultegra borrows heavily from its top-tier Dura-Ace group and if you're looking for an upgrade or building up a bike and can't go full carte blanche, the Ultegra Di2 ST-R8070 Shifters & Disc Brake Caliper Set is a terrific option that honestly offers the majority of us everything we need.
Using electronic shifters has another benefit when paired with hydro brakes, it takes up much less space than mechanical bits so the hoods are much more compact and lower profile and that's where we spend most of our time riding. The new rubber compound and tread used on the hoods is also designed to reduce vibration and improve grip, with or without gloves on, and sweaty hands refuse to slip while climbing out of the saddle or on rainy rides. The screw reach adjustment easily places the brake levers just where you need them for comfort and maximum control.
The shift buttons are now easier to reach from the hoods and in the drops and have a more positive click and are more distinguishable between upshift and downshift than previous versions. What we love most about Di2 is that shifting feels akin to clicking a mouse, only requiring about 2mm of movement. This requires much less focus and effort, especially for front shifting, so you can concentrate on riding and responding to attacks and not on executing the perfect shift. Both remote sprinter and climbing satellite shifters are available separately that plug into these shifters, allowing for further customization.
Now that Shimano has fully embraced road disc and slots the 8070's under the Ultegra dedicated road series, installation and syncing up with the rest of a Shimano Di2 group is typical of what we've come to expect from the firm. The brakes come pre-bled and if you're careful, you can shorten the hoses or route them internally if your frame and fork require, without a bleed. But even if you have to, it’s an easy affair and Shimano's choice of using paint and planet friendly mineral oil gets high praises from us. The R8070 calipers have excellent and well thought out design features like easy access bleed ports and top-loading pads. The calipers deliver power and modulation in spades and enjoy the IceTech technology that Shimano refined on its mountain bike brakes. Brake pads with cooling fins and ceramic pistons help dissipate heat and insulate so the brakes are as consistent at the bottom of a 7-mile descent with heavy braking as they are at the top. Shimano recommends using IceTech rotors (sold separately) with a stainless steel braking surface sandwiching an alloy core for the best performance and increased safety.
The Ultegra Di2 STI levers are compatible with Shimano E-Tube components and accessories including derailleurs, battery, junction boxes, and wires. The E-Tube software allows you to fully customize the group including shifting speed, number of shifts per click or hold, and control over what the buttons do.
- Ultegra-level hydraulic disc brake and electronic shift levers
- Race-worthy shift action from its most popular group
- Levers provide reach and stroke adjustment to dial in the feel
- Heat-dissipating features keep the braking constant and safe
- Low-profile hoods improve ergonomics
- Redesigned lever blades and paddles
- Bigger shift buttons with more positive clicks
- E-Tube technology customizes shifting