The new Shimano GRX Di2 RX827 is completely wireless using the same technique as with the recently launched Di2 MTB groupsets. The derailleur is not connected anymore to the bike battery but carries a small individual battery in the derailleur body.

The derailleur has an automatic ‘impact recovery’ that disconnects in case of major blows. According to Shimano the battery lasts about 700-1.000 km. After that, you need to remove it to recharge. The derailleur can be connected to the Shimano app via bluetooth.

The derailleur can be connected to all Shimano wireless 12-speed shifters in a 1×12 speed set-up. The only difference with the existing GRX 12-speed group is the new RX825 lever on the left for braking only. As a result, the grip is lighter at 188 grams than the 207.5 grams of the grip with switch electronics of the 2×12-speed setup.

The long-cased derailleur is designed according Shimano’s new Shadow ES principle. In addition, the whole has a wedge shape and is positioned under the frame as much as possible to ensure that the derailleur is ‘pushed away’ by possible obstacles.

Price* upgrade kit: € 499

More information: https://bike.shimano.com/nl-NL/products/series/grx.html

*Manufacturer price, this could vary by country, pls check your local supplier

Images/video: Shimano