Shimano 12-speed GRX finally gets Di2 and custom control levers that can operate GPS devices

 GRX RX825 dual controllers details.
GRX RX825 dual controllers details.

Shimano has announced a selection of new GRX RX825 Di2 components including newly designed dual control levers, 2 x 12-Speed GRX electronic shifting, and a Di2-equipped Shadow RD+ Rear Derailleur. The Japanese brand says these latest additions to its gravel bike groupset will deliver "optimal performance and enhanced gearing options" to the best gravel bikes.

GRX launched as the first gravel-specific groupset in 2019 and saw its first major evolution last year with the release of the mechanical 12-speed Shimano GRX RX820. We noted at the time that a fully electronic GRX Di2 option would likely come soon, and our crystal ball speculating has now come true.

These new additions also complete the line-up of Shimano’s Di2 electric 12-speed gravel component family, and we had a look over the details to see what they'll bring to the gravel riding table.

Close up of the Shimano GRX RX825 Di2 front derailleur
Close up of the Shimano GRX RX825 Di2 front derailleur

Di2 Front Derailleur

First up is a new electric shifting option added to the 2 x 12 GRX groupset. Riders can now choose to add Di2 shifting performance to their front derailleur, and like with the RX820 mechanical version, they can tailor the gearing to suit their gravel riding needs.

The GRX RX825 Di2 front derailleur is compatible with a host of Shimano chainrings and cassettes, including the RX820 48/31-tooth chainrings or there is the choice of the RX610 crank and its 46/30-tooth chainrings. Compatible Shimano cassettes include 11-36T HG710 or 11-34T R9200, R8100, and R7100 options.

Pricing for the Di2 RX825 GRX Di2 Front Derailleur is $209.99 / £184.99 and weighs in at a claimed 142g.

Close up details of the Shimano Shadow RD+ Di2 Rear Derailleur
Close up details of the Shimano Shadow RD+ Di2 Rear Derailleur

Shadow RD+ Di2 Rear Derailleur

The RX825 rear derailleur features Shimano’s Shadow RD+ technology and now like its front derailleur sibling, it also gets the Di2 makeover. Shadow RD+ has its convenient on/off switch that makes removing the rear wheel easy when turned off. When on, the drivetrain is under tension which stabilizes the chain, making for a quieter ride and precise shifting.

Shimano says the rear derailleur is the communication hub of the drivetrain, communicating wirelessly with the shift levers, and is compatible with the best cycle computers, and the Shimano E-Tube Project Cyclist app. It also houses the system’s charge port and the multi-function button which allows riders to easily check battery level, pair via Bluetooth, and enter adjustment mode for both derailleurs.

The Shadow RD+ RX825 Di2 Rear Derailleur weighs in at a claimed 310g and is compatible with 11-34T and 11-36T cassettes priced at $409.99 / £324.99.

Details of the Shimano GRX RX825 shifters
Details of the Shimano GRX RX825 shifters

Updated Shimano Di2 levers

The most interesting addition is the newly designed wireless Di2 connectivity dual control levers that are said to be refined for comfort and control. Shimano also adds that the new levers have a "gravel-optimized body shape cross-section" which apparently will make for seamless integration with the best gravel handlebars. The new shifters also have a rounder shape and should make the transfer from bar to hood smoother, create a larger surface area for hands, and help eliminate pressure points.

As with the original GRX RX815 Di2, the new offerings come with three Di2 buttons per lever and give loads of customization options from another shift location or for scrolling through screens on a cycle computer.

For riders requiring even more control, accessory shift buttons can also be added. Shimano’s satellite shifters can be placed anywhere on the bars, and like the third button on the GRX levers, these satellite switches can be assigned various functions including shifting either derailleur, to control compatible lights and cycle computers, or as a lap button during workouts.

The new RX825 dual controllers are compatible with existing 12-speed GRX components and pair seamlessly with the new Di2 front and rear derailleurs. The replaceable coin cell batteries have an expected lifespan of 3.5 to 4 years and the RX825 dual controllers weigh in at a claimed 415g per pair. Pricing is $765.99 / £599.98 per pair.

GRX RX825 dual controllers details
GRX RX825 dual controllers details

Availabilty

The entire range of GRX RX825 Di2 components are available now from Shimano and its stockists. For further information visit Shimano.com.