GRX RD-RX825 Di2 Rear Derailleur, 12-speed

United in Gravel!
With a clear focus on the heart and soul of gravel biking, SHIMANO’s electronic GRX series now gets a 12-speed update to deliver top performance!
Simplicity and reliability build the basis for the new 12-speed GRX line-up and allow you to enjoy off-road adventures of a special kind!

With the GRX Di2 RX825 12-speed rear derailleur as the master unit, the Japanese branch giant brings proven and reliable technologies to your gravel racer.
For example, the ingenious developers at SHIMANO have taken inspiration from the mountain bike sector and integrated the tried-and-tested Shadow RD+ technology. The forward and reverse movement of the RD-RX825 Di2 rear derailleur is slowed down considerably by the selectable friction damper. This significantly reduces the risk of chain bouncing and jump off and shifting into the wrong gear, while significantly reducing chain noise.
This guarantees silent, smooth, precise and reliable electronic gear changes in challenging terrain. Whether riding off tarmac roads and on dusty gravel roads, going on a bikepacking adventure with lots of luggage, doing classic cyclocross or simply commuting to work.

Details:
Wireless electronic 12-speed rear derailleur
Di2 wireless chip with low interference, high processing speed and low power consumption
Shadow RD+ technology (friction damper)
Compatible with Direct Mount
4 fluorine-coated joint bushings
SD300 E-Tube Port: slimmer cables for less weight and easier routing
Bluetooth LE compatible: can be wirelessly customised via E-Tube app for smartphone & tablet
Compatible with ANT+: transmission of data (e.g. current gear) to compatible bike computers
Status LED for system information and battery level displays at the touch of a button
Splash-proof charging port for charging the central Di2 system battery
Also suitable for wired setup

Technical details:
Intended use: Gravel, Road, Cyclocross
Series: GRX Di2
Material: aluminium, fibreglass composite, stainless steel, steel
Compatibility: SHIMANO Di2 connectivity wireless, SHIMANO Di2 connectivity wired
Gears: 12-speed
Largest sprocket max.: 36 teeth
Largest sprocket min.: 34 teeth
Smallest sprocket max.: 11 teeth
Smallest sprocket min.: 11 teeth
Max. front difference: 17 teeth
Total capacity: 40 teeth
Compatible chains: SHIMANO HG 12-speed
Slots: 1 EW-SD300 E-Tube port, 1 EW-EC300 charging port
Function key: yes
Weight: approx. 310 g

In the box:
1 SHIMANO GRX RD-RX825 Di2 rear derailleur