Today, Shimano launches its new 2×12 GRX Di2 groupset, the GRX Di2 RX825. Having previously upgraded its GRX groups to 12-speed, Shimano has now added the electric variant. A new group means an upgrade to the brake levers. According to Shimano, for more comfort and control. There is also a Shimano SHADOW RD+ rear derailleur better shifting and a new front derailleur, completely optimised so you can shift quickly on all surfaces.
Even better gear shifting
Shimano's new gravel group thus adds electric shifting to the 2 x 12 GRX group launched last year. It is also easy to upgrade the existing RX820 group with the new GRX RX825 Di2 gear levers, available satellite shifters, front derailleur and rear derailleur.
Customise to your own taste
As with the RX820 mechanical components, riders can customise their gearing with the 48/31-tooth chainrings or choose to use the RX610 crank and its 46/30-tooth chainrings. Similarly, riders can choose from an 11-36T or 11-34T cassette for a wide gear range with small gear steps so they can run a comfortable cadence.
Battery
One of the things that makes Shimano different from competitor SRAM is the battery. As with the DURA-ACE, Ultegra and 105 groups, there is one battery, which is usually tucked into the seatpost. With the competitor, each derailleur has its own battery. The big difference: if the battery is empty, you have to recharge it completely (at the plug). With the competitor, you have two separate batteries that you can quickly replace. The advantage if you have a Wahoo, for example: then you can link your navigation with the Di2 and always know how much battery you have (and when you need to recharge). The battery in my Ultegra Di2 will do for 1000s of kilometres, so 'pas de probleme'.
Read also: Shimano vs Campagnolo vs SRAM: What are the differences?
Wireless cockpit
Whereas gravel used to be quite rugged and chunky in execution, the bikes are becoming increasingly styled and that includes a wireless cockpit. The brake levers have the now familiar ribbed surface and anti-slip, giving you more grip and therefore a more confident ride. no matter how snappy the ride gets. Thereby, like the GRX 815, you have a second Di2 button on the inside of the lever. Nice work Shimano
E-tube and Front Shift Next
Using Shimano's E-TUBE PROJECT Cyclist app, cyclists can choose between different multi-shift shift intervals, customise shift button assignments (which buttons perform which functions), programme different automatic shift modes such as Synchronous and Semi-Synchronous shifting, and fine-tune shifting.The launch of the RX825 also coincides with the debut of Shimano's new FRONT SHIFT NEXT functionality. We're not quite clear yet what this entails, but I'm sure we'll find out soon enough.
Technical details
SHIMANO SHADOW RD+ rear derailleur
The RX825 rear derailleur features Shimano's well-known SHADOW RD+ technology. With its convenient on/off switch, SHADOW RD+ makes removing the rear wheel easy when it is off. When it is on, the drivetrain is under extra tension. Result: quieter cycling and better shifting
As with Shimano's other 12-speed Di2, the rear derailleur is also the drivetrain's communication hub, communicating wirelessly with the levers, various bike computers and E-TUBE PROJECT app. Here you will also find the system's charging point again and the multifunction button that allows you to easily check the battery level, pair via Bluetooth and activate the adjustment mode for both derailleurs.
RD-RX825 Rear derailleur
- SHIMANO SHADOW RD+ chain stabilisation
- Integrated D-FLY connectivity and charging
- 12 gears
- Compatible with 11-34T and 11-36T cassettes
- Weight: 310 grams
Chain with more space
Like the very first GRX groups, the RX825 system has a wider chainline of +2.5 mm for better tyre clearance. This is especially useful with the trend towards wider tyres and events where mud is expected.
FD-RX825 front derailleur
- Chainline +2.5 mm compared to conventional road FD
- Wider tyre clearance
- 2 x 12 gears
- Weight: 142 grams
More information on the new group can be found at shimano's site
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