SHIMANO GRX Di2 disc brake set shift/brake lever ST-RX825 + BR-RX820 Flat Mount | 2x12-speed | single
With the GRX, Shimano launched the first gravel-specific groupset on the market. Since then, the range of applications and the range of gravel bikes has expanded significantly. Shimano has responded to this development by updating the GRX groupset. It now comes with modern Di2 technology and a 12-speed drivetrain. The high level of functionality and quality reflects the Japanese company's many years of experience.
Technically, the GRX Di2 is similar to the current road bike groupsets. The shifting commands are transmitted wirelessly to the front derailleur and rear derailleur. The latter are connected to a central battery, which can be concealed in the seat post, for example. The 12-speed drivetrain has also been adopted and enables a wider gear range. This makes long uphill rides very comfortable even for less trained riders.
The GRX shift/brake levers have a grip geometry and surface texture specially optimized for gravel use. The upper hump has been raised to prevent you from slipping forwards on rough surfaces, and the shape has been optimized for wide-opening.And to prevent your hands from sliding back and forth even when riding in the rain, a non-slip material has been selected which also has good damping properties and therefore increases comfort.
Shifting is done at the touch of a button. This is quick and effortless. The pressure point is so precise that unintentional gear changes are practically impossible. This wireless system is also fully customizable with the help of the Shimano E-Tube app. Among other things, the shifting speed can be set, a fully or semi-synchronous shifting mode can be selected and the program buttons on the lever can be assigned specific functions. Energy consumption is also very low. According to Shimano, the two CR1632 button cells should supply the electronics with power for over 3 years. The absence of wiring not only simplifies installation, but also gives you a neat and tidy cockpit.
The brake lever has also been designed so that you can stop quickly at any time from any grip position. It is slightly bent inwards and the axis of the lever has been moved upwards. This improves the ergonomics and at the same time reduces the necessary manual force. In addition, the reach of the brake lever can be individually adjusted so that bikers with smaller hands can also ride safely.
The flat-mount brake calliper improves braking performance and modulation under all conditions. Maintenance work, such as bleeding or changing pads, is also easy to carry out. The L05A brake pads with cooling fins help to keep brake temperatures low, especially on long descents.
Technical data:
Shift/brake lever material: aluminum, plastic
Technology: Reach Adjust, Dual Control Lever, E-Tube
Gears: 2x12
Reach adjustment: yes, integrated (with tool)
Brake caliper material: Aluminum
Brake fluid: Mineral oil
Mounting: Flat Mount
Bolt length: n/a
recommended brake rotors: Shimano RT-CL800
Brake pads: L05A-RF synthetic resin (with cooling fins)
Brake hose length: 1000 mm (front) or 1700 mm (rear)
Color: black-anthracite
Weight according to manufacturer: n.a.
Weight self-weighed: 388g (front), 387g (rear)
Scope of delivery: 1x shift/brake lever unit incl. brake calliper and hose (filled) | left - 2x OR right - 12-speed