Check Di2 shifter battery level and replace it
12-speed wireless Di2 shifter batteries last about two years, and this page will teach you how to check the battery level and replace the battery itself.
Disc Brake Dual Control Lever (Wireless)
GRX ST-RX825
Twelve-speed GRX Shift levers feature one SD300 port, one satellite shifter port, and three shift buttons.
The third button isn't on top of the shifter but on the inside, where you would rest your thumbs.
Like the 105 Di2 shifters, these GRX units take two CR1632 batteries. They should last for about 3.5 - 4 years.
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Wired compatibility
If you've looked at the compatibility information for 12-speed Di2 then you might've noticed that ST-RX825 has no official wired compatibility.
Regardless of what the compatibility information says, you can in fact wire up these shifters no problem. They'll show up in E-Tube Project as you'd expect, and shift wired just fine.
Specifications
- Model code: ST-RX825
- Series: GRX (RX825)
- Weight: 207g (per lever)
- Speeds: 12
- SD300 ports: 1
- Satellite Shifter ports: 1
- Battery: CR1632 (2 per lever)
- Wired shifting: Yes (optional)
- Wireless shifting: Yes
- Servo wave: Yes
- Free stroke adjust: Yes
- Reach adjust: Yes
- Brake type: Disc
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Pair 12-speed Wireless Di2 Shifters
I'll show you two different methods of pairing 12-speed Di2 wireless shift levers - using the mobile app and using wires.
Unpair 12-speed Wireless Di2 Shifters
Unpairing 12-speed Di2 wireless shift levers can be done using the mobile app or using the SM-PCE02 and E-Tube Project for Windows. This page describes both methods of unpairing wireless shifters.
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