SHIMANO GRX 820 complete groupset 1x12 Unstoppable | 10-51 teeth 172.5 mm 40 teeth
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 expanding the range of the GRX groupset. With now 12 sprockets on the rear wheel and the option to choose between a 1x and 2x setup, you can adapt your drivetrain even better to your needs. You can get the GRX 820 complete groupset here at R2-Bike.com at an absolute top price. Simply buy, install and ride off.
Shifter/brake lever SHIMANO GRX BL-RX820 / ST-RX820 + brake caliper BR-RX820 Flat Mount
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 forward on rough surfaces. A recessed thumb recess ensures a firm grip on difficult terrain at all times. 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.
As usual, the dual-control lever of the GRX series offers outstanding ergonomics. The crisp shifting operations can be carried out quickly, precisely and with little finger force. This means you never lose control of your bike, even in hectic situations.
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 axle of the lever has been moved upwards. This improves ergonomics and at the same time reduces the necessary hand force. The Servowave Action technology allows you a short brake lever travel until the pads make contact with the brake disk. Once the brake pad is in contact, the force transmission factor increases rapidly, so that a large part of the lever travel is still available for targeted braking force dosage. 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 L03A brake pads with cooling fins help to keep braking temperatures low, especially on long descents.
Brake rotor SHIMANO Deore XT Center Lock RT-MT800 | 160 mm + 160 mm
With Ice-Tech cooling technology, the RT-MT800 brake rotor ensures constant braking performance even on long descents. The brake rotor is characterized by a three-layer sandwich construction. The stainless steel flanks with an aluminum core offer significantly improved heat dissipation. This allows the temperature to be reduced by around 100 °C.
In addition, the FREEZA aluminum cooling fins reduce the system temperature by a further 50 °C due to their increased surface area. The increased heat dissipation means that smaller brake discs can be fitted than usual. The service life of the brake pad is also significantly extended.
As is typical for Shimano, the rotors are suitable for the Center-Lock mount, which enables quick and easy installation, provides a secure hold and ensures a clean and compact look. A lighter aluminum carrier saves a few grams of weight compared to the previous version.
Crank SHIMANO GRX FC-RX820-1 | 1x12-speed | 40 teeth | Q-factor 151 mm | crank arm length 172.5 mm
With its chainline of 49,7 mm, the GRX 1x crank creates space for wide tires in the frame and positions the chainring optimally for the 12-speed cassette. In conjunction with the compatible Shimano 12-speed cassettes with 10-51 or 10-45 teeth, the GRX drivetrain allows you to choose between a maximum range for the steepest ramps and a narrower gear ratio for flatter terrain.
Rear derailleur SHIMANO GRX RD-RX822-SGS Shadow+ long cage | 1x12-speed
The RX822-SGS rear derailleur has been specially developed for the GRX 1x12 drivetrain with Shimano cassettes with 10-51 teeth for Shimano Micro Spline freehub bodies. This drivetrain offers you the maximum range for the steepest ramps and you can enjoy the advantages of a 1x drivetrain.
Thanks to the built-in Shadow RD+ chain stabilizer, the chain stays securely on the chainring even on the roughest gravel trails. As you would expect from Shimano, shifting is quick and precise with little finger force. Even under adverse conditions, the chain shifts reliably from one sprocket to the next. In order to be able to adjust the rear derailleur optimally, it has its own adjustment screw, which can be used to adjust the tension of the Bowden cable.
Thanks to the compact Shadow design, the rear derailleur sits closer to the frame. This slim low-profile design not only cuts a fine figure visually, but also protects the rear derailleur from damage or branches reaching into the path in the event of a fall.
Cassette SHIMANO Deore XT cassette CS-M8100 | 12-speed 10-51 teeth
Smooth and precise shifting has always been a hallmark of Shimano cassettes. In the Hyperglide cassettes of the last generations, the sprockets were positioned in such a way that the chain runs extremely smoothly and with little vibration, especially when shifting to a larger sprocket. With the XTR M8100 cassette, Shimano introduces Hyperglide+. Thanks to this technology, shifting now runs just as smoothly even when shifting into a heavier gear and is 1/3 faster than with the CS-M8000 cassette.
In the construction of the cassette, Shimano relies on a material mix of steel and aluminum for the sprockets. While the ten small sprockets with the lowest chain wrap and highest load are made of steel, the two large sprockets are made of aluminum. This load-dependent use of material leads to even wear of the cassette and also extends the service life of the chain. The cassette is held together by an aluminum spider.
SHIMANO Deore XT | Ultegra CN-M8100 12-speed chain | 126 links with chain lock
The CN-M8100 chain is specially designed for the M8100 chainrings and cassettes. Thanks to cut-outs on the inside of the plates, the chain harmonizes perfectly with the Dynamic Chain Engagement+ (DCE+) narrow-wide tooth profiles of the new XT chainrings. The design results in a tighter fit of the chain on the teeth. Vibrations are avoided and the smoother chain run is not only noticeable when pedaling, but is also noticeable acoustically thanks to a 4 dB quieter drivetrain. Thanks to a new chrome-plated surface in combination with the proven SIL-TEC coating, the service life of the chain has been kept at the same level as the M8000 chain, despite the smaller outer width.
Technical data:
Area of application: Gravel
Material: Aluminum, plastic
Gears: 1x12
Brake type: hydraulic disc brake
Brake mounting: Flatmount, optional adapter may be required depending on fork and frame
Crankshaft: 24 mm
Crank length: 172.5 mm
Chainring gradation: 40 teeth
Chainring mount: 4-arm asymmetrical | 110 mm
Cassette gradation: 10-51 teeth
Freehub body compatibility: Shimano Micro Spline
Color: black, grey, silver
Weight according to manufacturer: 2481g
Weight self-weighed:
Scope of delivery:
1x SHIMANO brake lever GRX BL-RX820 + brake caliper BR-RX820 Flat Mount front
1x SHIMANO shift / brake lever GRX ST-RX820 + brake caliper BR-RX820 flat mount rear, WITHOUT flat mount adapter
2x SHIMANO brake rotor Deore XT Center Lock RT-MT800 | 160 mm
1x SHIMANO crank GRX FC-RX820-1 | 1x12-speed | 40 teeth | Q-factor 151 mm | crank arm length 172.5 mm
1x SHIMANO rear derailleur GRX RD-RX822-SGS Shadow+ long cage | 1x12-speed
1x SHIMANO Deore XT CS-M8100 cassette | 12-speed 10-51 teeth
1x SHIMANO chain Deore XT | Ultegra CN-M8100 12-speed | 126 links with chain lock
WITHOUT BOTTOM BRACKET
WITHOUT brake adapter
Notes:
Delivery without rear brake rotor adapter. Before installation, please check which disc size the mounts on your frame are designed for.
You can find the recommended bleeding kit and brake fluid for connecting the brakes in our store.
SHIMANO Professional Bleed Kit for Disc Brakes TL-BR001/TL-BR002/TL-BR003available from stock
