Shimano has updated their gravel-specific electronic GRX Di2 groupset to a 12-speed configuration with the latest in electronic shifting technology.
This new GRX RX825 Di2 groupset features many innovations that can also be found in the Shimano Dura-Ace Di2 and Shimano Ultegra Di2 groupsets. In terms of braking technology, Shimano sticks to their current reliable technology, which makes sense since the GRX was already a pioneer with the Servo Wave technology. This technology was later also implemented in the 12-speed groupsets for road bikes.
Bluetooth derailleur
The GRX RX825 derailleur from Shimano is equipped with 12-speed and has Bluetooth functionality. This derailleur is suitable for cassettes with a largest cog of 36 teeth. Unlike its predecessor, which offered a choice between a short or long cage and was compatible with cassettes up to 42 teeth, this new derailleur does not have cage options. It weighs 310 grams according to Shimano and, like the derailleurs from the road groups, has a charging port and a built-in Bluetooth connector. With a small button on the derailleur you can check the battery status. By holding this button down for a longer period, you can connect the e-tube app to adjust the derailleur or update the firmware.
Crankset especially for Gravel
The RX825 group comes with a double crankset. Although the front derailleur has undergone only minimal changes in appearance, it has become 10 grams heavier. An important feature of the GRX group is that the chainline offers 2.5 mm more space compared to the road groupsets. This ensures that both derailleurs are further away from the frame, which creates space for wider tires. In addition, this extra space also helps to reduce mud accumulation, which is a great advantage when riding gravel.
Shifters with anti-slip
In addition to the same shape, the anti-slip coating on the brake levers has also been retained, which is a good choice. The shifters have a third button on the inside of the hoods, which you can set to your own preference. You can use this button to scroll through your Garmin, for example, or to activate additional shifting options by connecting it to your derailleur. For even more options, you can also connect satellite or sprint shifters. These are wired to your shifter, so that you can, for example, shift with your thumb while riding in the drops.
KFCRX8202CX81 SHIMANO FC GRX FC-RX820-12 170 48-31
KFCRX8202DX81 SHIMANO FC GRX FC-RX820-12 172.5 48-31
KRDRX825A SHIMANO REAR DER. RD-RX825 GRX 12S
KFDRX825F SHIMANO FRONT DER FD-RX825 GRX 12S
KRX8251DLF6RX075A SHIMANO SHIFTER GRX STRX825+BRRX820 FR75
KRX8251DLF6RX085A SHIMANO SHIFTER GRX STRX825+BRRX820 FR85
KRX8251DRRDRX145A SHIMANO SHIFTER GRX STRX825+BRRX820 R145
KRX8251DRRDRX155A SHIMANO SHIFTER GRX STRX825+BRRX820 R155
KBTDN3001 SHIMANO BATTERY BT-DN300 BUILT-IN EU
KCSHG71012136 SHIMANO CASSETTE CS-HG710-12 12S 11-36 KRTMT800SI SHIMANO ROTOR RTMT800 S 160 W/LOCKRING KCNM7100114Q SHIMANO CHAIN CN-M7100 12S 114L W/Q-LINK KSMBB7241B SHIMANO BB BB72 P-FIT41 ROAD KEWSD3 00IL065 SHIMANO ELECTRIC WIRE EWSD300 650MM KEWSD300IL120 SHIMANO ELECTRIC WIRE EW-SD300-I 1200MM KEWEC300A SHIMANO CHARGING CABLE EW-EC300 1700