Shimano’s new Ultegra Di2 electronic-only groupset delivers Dura-Ace performance for less cash
Shimano's second-tier road groupset gets 12-speed gearing, wireless shifters and a power meter option

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Hot on the heels of Shimano’s new flagship Dura-Ace Di2 launch comes Ultegra Di2 R8100.
Like Shimano Dura-Ace Di2 R9200, the new Ultegra road bike groupset is 12-speed, available with rim or disc brakes and semi-wireless (in the disc brake variation). Crucially, there’s also no mechanical option for Shimano’s new second-tier groupset.
As Shimano’s top-tier groupset, Dura-Ace historically launches ahead of Ultegra, which then typically follows a year later. This time round, however, the Japanese firm is launching both groupsets at the same time.
As a result, the new Ultegra groupset series brings all the technical advantages of the latest 12-speed, semi-wireless pro-level Dura-Ace system at a more accessible price point. (The rim brake Ultegra Di2 groupset is still fully wired).
Ultegra Di2 isn’t exactly an ‘every person’ groupset, but with current R8070-equipped bikes appearing from around £4,000 it’s in the realm of your serious cyclist, rather than the WorldTour-level price tags associated with Dura-Ace Di2.
We’ll focus on Ultegra Di2 in this story. If you want to read about Shimano’s crème de la crème, head to our news story and first ride impressions on the new Dura-Ace groupset.
10 firsts for the new Shimano Ultegra Di2
The latest Ultegra Di2 brings with it a number of firsts and updates for Shimano’s second-tier road groupset, including 12-speed gearing, wireless shifters, an Ultegra-level power meter option and more.
- Like Dura-Ace, the new R8100 series moves to 12-speed
- For the first time, it’s electronic-only – there’s no mechanical option
- Wireless disc brake shifters make for cleaner cockpits (the rim brake groupset is still fully wired)
- Built-in Bluetooth brings out-of-the-box tuning
- There’s an Ultegra-level power meter option
- Full carbon tubeless wheelsets
- Direct charging means no junction boxes
- Servo Wave braking technology borrowed from GRX Di2
- Wider rotor clearances for quieter brakes
- New lever ergonomics for improved braking from the hoods and shifting from the drops
Wireless, sort of

The new Ultegra R8100 is electronic-only and, in the disc brake version, wirelessly communicates gear-change inputs from the shifters while maintaining a wired connection from the rear derailleur and front derailleur to a battery mounted in the seat tube.
The previous battery won’t carry over to R8100 because Shimano has designed the new system around a smaller diameter wiring loom (SD-300).
It’s not the first time we’ve seen this configuration. Back in 2017, FSA’s K-Force W.E. (wireless electronic) group brought us a wireless shifter-derailleur interface and central battery solution. (SRAM, of course, has long offered its fully wireless eTap AXS groupsets.)
Shimano’s system promises high-security and fast processing, with a low power consumption chip circuit and the same internals as Dura-Ace.
Power consumption is the main reason Shimano has persisted with the single, larger volume battery and tells us the new BT-DN300 battery should last for 1,000km between charges, while the coin-cell CR1632 batteries in the shifters should be good for 1.5 to 2 years of use.Unlike current Di2 systems (you can read our Shimano Ultegra Di2 R8050/R8070 review), the new Ultegra charges direct from the rear mech, so no junction box is required when configuring a bike.
Alongside the charge port being added to the rear derailleur, the rear mech also gets a function button to allow you to switch between shifting modes (synchronised and semi-synchro) without the need to connect to Shimano’s E-Tube app.
Synchronised shifting means the most efficient chainring is automatically selected on the front derailleur in synchronisation with rear derailleur gear shifting, while semi-synchro is when the system automatically adjusts the gear on the rear cassette when a front shift is made.