Shimano GRX Di2 RX825 2x12-speed Group Disc

The GRX Di2 is Shimano's new 2x12-speed electronic groupset for gravel bikes, a combination of Shimano's unrivalled electronic shifting technology and a wide range of gear ratio options. Gravel tours, competitions or bikepacking adventures can now be tackled with even more confidence and comfort. After all, Shimano developed every single component with the special needs of gravel bikers in mind, whether they are travelling on lonely forest trails, taking part in a gravel race or simply want to enjoy the great outdoors undisturbed.

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Scope of delivery - Shimano GRX Di2 RX825 2x12-speed Group Disc

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For your riding freedom: the GRX Di2 RX825 2x12-speed disc group from Shimano

Gravel cycling is not meant to be overly complicated. The heart and soul of cycling’s drop bar, dirt road discipline is rooted in simplicity, inclusivity, and adventure. No ride is out of bounds. All are welcome to join. Gear should be functional and reliable but need not break the bank. That’s why whether you’re a grizzled gravel cycling veteran or brand new to the road (or trail) less traveled, you’ll appreciate the latest iteration of Shimano’s groundbreaking—and industry-first-gravel-specific GRX component group. Designed to help you get the most from your next unpaved adventure, RX825 delivers top-tier performance without an over-the-top price.

For riders seeking the best of both worlds, the new 2x12 RX825 UNDROPPABLE drivetrain is the choice. Utilizing a gravel-optimized 48/31 or 46/30 front chainring paired with an 11-34 or 11-36 cassette, this setup delivers an ultra-wide gear range so you can spin a comfortable cadence whether cruising the flats, smashing endless dirt road rollers, or tackling a massive backcountry climb.

Alongside this suite of gravel-optimized gearing options is the new ST-RX825 brake/shift levers. Specifically designed for use with flared handlebars that are a gravel-cycling staple, the new lever body design features anti-slip texturing on the tops and dramatically improved ergonomics that lessen pressure on your palms. Together, these changes increase comfort and control so you can fearlessly tackle tricky terrain or focus on the rolling gravel road ahead.

This setup delivers precise shifting both front and rear and an integrated SHADOW PLUS chain stabilization for ultimate security over bumpy terrain. The gravel-specific 2x12 option maintains tighter rear cassette gear steps, ideal for subtle cadence changes during competitive racing and spirited weekend group rides.

The new wireless Di2 platform ensures fast and smooth shifting at the front derailleur. It also offers a choice between manual shifting and synchronised shift assist modes - SEMI-SYNCHRO or FULL-SYNCHRO - that feel like your own personal assistant! In SEMI-SYNCHRO mode, the rear derailleur automatically adjusts to avoid big jumps in gear ratio so you can maintain your cadence and rhythm. In FULL-SYNCHRO mode, the rear derailleur and front derailleur work together harmoniously so that you always have the right gear engaged and no longer have to worry about it. Seamless communication with the rear derailleur combined with programmed chain guide control minimises the risk of the chain jumping off.
It's up to you how often you want to think about the gear ratio!In the E-TUBE app, you can select the fully and semi-synchronised shifting functions. Thanks to the digital precision of the electronic shifting and its coordinated communication between the front and rear derailleurs, the SHIMANO GRX front derailleur offers an excellent shifting experience.

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Shimano GRX FC-RX820 2x12-speed Crank 48/31

The new GRX FC-RX820-2 HOLLOWTECH II 2x12-speed crankset offers the perfect synthesis of light weight and high efficiency for mixed terrain riding. The transmission options address the specific requirements of Gravel and provide tighter gradations for a smooth rhythm.

Features

• Optimal gearing for different surfaces and riding styles
• Gravel-tuned gear ratio helps maintain rhythm on uneven terrain with wider tires
• Wide front gear range
• 17 teeth difference

Product features

• Use: Gravel, Cyclocross
• Group: GRX
• Model: FC-RX820-2
• Gradation: 48/31 teeth
• Q-Factor: 151mm
• Case width: 68 / 70mm
• Gear ratios front: 2-speed
• Rear gears: 12-speed
• Mounting: Hollowtech II
• Compatible chain: 12-speed HG
• 4-arm crank spider: Yes
• Bolt circle: 110/80mm
• Chainline: 47mm
• Recommended bottom bracket Pressfit: SM-BB72
• Recommended bottom bracket BSA: SM-BBR60

Crank arm length (choose variant)

• 170mm
• 172,5mm
• 175mm

Material

• Crank arms: aluminum, anodized
• Crank axle: steel, plated
• Chainrings: aluminum anodized

Color

• Series color

Weight

• approx. 721g/172.5mm (manufacturer information)

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Shimano GRX Di2 ST-RX825 2x12-speed STI unit + BR-RX820 Disc Brake Set

A central concern of Gravel riders is a reliable braking system with sufficient power reserves, the new Shimano GRX Di2 2 x 12-speed ST-RX825 STI with BR-RX820 Flat-Mount calipers for hydraulic disc brake is characterized by excellent deceleration performance to maintain control on steep, demanding or even surprising descents.

Features

• Wireless Di2 Connectivity
• Clean cockpit: Wireless connection enhances the aesthetic of your bike while keeping shifting lightning fast
• Longer lasting. Uses two CR1632 batteries (battery life: 3.5 to 4 years)
• Three Di2 buttons per lever for E-TUBE PROJECT Cyclist app customization
• Compatible with satellite shifters
• Greater mixed-terrain control
• Gravel inspired lever and bracket ergonomics
• Anti-slip brake lever
• Same light shifting operation as top tier road systems
• Never hesitate to tackle rough surfaces
• Excellent heat dissipation
• ICE TECHNOLOGIES
• Flat mount
• Simple set up and maintenance
• Convenient tool access
• Easy hose joint system (J-kit)
• Simple wheel replacement
• Easy and clean bleeding system
• ONE WAY BLEEDING
• Included in delivery: 1 x GRX Di2 ST-RX825 2x12-speed STI unit set, 2 x GRX BR-RX820 flat-mount brake caliper, 1 x flat-mount adapter 140mm/160mm, 2 x brake pads L05A-RF resin with cooling fins, 2 x brake line SM-BH90-JK-SS 1000mm / 1700mm (can be shortened), 4 x mounting screw forr brake caliper (for rear 2 x 38mm), 2 x cable connection kit
• J-Kit - SM-BH90-JK-SS brake lines are filled with mineral oil and pre-assembled on BR-RX820 calipers!

Product features

• Use: Gravel, Cyclocross
• Group: GRX Di2 RX825
• Model: ST-RX825
• Type: Dual-Control (STI)
• Handlebar mounting: left/right
• Gear front: 2-speed
• Gear rear: 12-speed
• Optical gear display: No
• Lever reach adjust: Yes, with tool
• Handlebar diameter: 23.8mm/24.2mm
• Brake-type: Hydraulic Disc Brake
• Brake caliper: BR-RX820
• Brake mounting: Flat-Mount
• Brake pads: L05A-RF Resin with Fin
• Brake hose: SM-BH90-JK-SS front 1000mm / rear 1700mm (shortable)
• One-Way bleeding: Yes
• Brake fluid: Mineral oil
• Recommended brake rotor: SM-RT64, SM-RT70, SM-RT800
• Compatible electric wire: EW-SD300
• E-tube Project: Yes
• E-tube port (pcs): each 1
• E-tube connector (pcs): 0
• Di2 Wireless-Chip: Yes
• Battery: each CR1632 x 2

Material

• Lever: Aluminum
• Brake caliper: Aluminum

Color

• Series color

Weight

• approx. 415g/ST-RX825 pair | 267g/BR-RX820 pair (manufacturer information)

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Shimano GRX Di2 FD-RX825 2x12-speed Front Derailleur Braze-On

The SHIMANO GRX Di2 RX-825-F 2 x 12-speed front derailleur offers precise and coordinated shifting. Features include a 2.5 mm outwardly offset chainline that provides greater tire clearance for riding on mixed terrain.

Features

• Powerful, accurate, smooth front shifting
• Programmed chain guide control by automatic trim
• SHIMANO SYNCHRONIZED SHIFT
• Manual, full- and semi-synchronized shifting program
• Chainline +2.5mm vs. conventional road FD
• Compatible with up to 42mm tires
• Wider tire clearance
• Wider range front gearing 17T

Product features

• Use: Gravel, Cyclocross
• Group: GRX Di2 RX825
• Model: FD-RX825-F
• Mounting: Brazed-on
• Cable route type: Down-Pull
• Gear front: 2-speed
• Gear rear: 12-speed
• Top gear teeth: 48T
• Total capacity: 17T
• Compatible chain: 12-speed HG
• Chain stay angle: 63-66°
• Chain line: 47mm
• Compatible electric wire: EW-SD300
• Firmware update by E-tube Project: Yes
• E-tube port (pcs): 1
• E-tube connector (pcs): 0
• Di2 Wireless-Chip: No

Material

• Aluminum
• Steel
• Fiberglass reinforced plastic

Color

• Series color

Weight

• approx. 142g (manufacturer information)

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Shimano GRX Di2 RD-RX825 2x12-speed Rear Derailleur

The SHIMANO GRX Di2 RD-RX825 2 x 12-speed rear derailleur with integrated chain stabilizer ensures quiet, safe and precise shifting on mixed terrain. For riding on smooth surfaces, the chain stabilizer can be deactivated using the ON/OFF switch on the rear derailleur. The RD-RX825 rear derailleur is compatible with cassettes with a maximum of 36 teeth on the largest sprocket.

Features

• Silent and secure rear shifting on rough terrain
• Adjustable chain stabilizer prevents chain slap and drops
• SHIMANO SHADOW RD+
• Smooth and reliable shifting on mixed surfaces
• ON/OFF stabilizer switch matches terrain
• Compact design includes an integrated wireless unit, charger, and switch
• LED status indicator
• Battery indicator
• Pairing
• Adjust mode, etc.

Product features

• Use: Gravel, Cyclocross
• Group: GRX Di2 RX825
• Model: RD-RX825
• Mount: Direct attachment (Conventional)
• Technology: Shadow RD+
• Gear front: 2-speed
• Gear rear: 12-speed
• Compatible Chain: 12-speed HG
• Max. teeth large sprocket: 36T
• Min. teeth large sprocket: 34T
• Max. teeth small sprocket: 11T
• Min. teeth small sprocket: 11T
• Max. Front Difference: 17T
• Total Capacity: 40T
• Compatible electric wire: EW-SD300
• Firmware update by E-tube Project: Yes
• E-tube port (pcs): 1
• E-tube connector (pcs): 0
• Di2 Wireless-Chip: Yes

Material

• Aluminum
• Steel
• Fiberglass reinforced plastic

Color

• Series color

Weight

• approx. 310g (manufacturer information)

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Shimano CS-R8100 / CS-HG710 12-speed Cassettes

The Shimano CS-R8100-12 (11-34) and CS-HG710-12 (11-36) are the matching 12-speed cassettes to the new GRX RX825 group. Compatible with new HG L2 road 12-speed FREEHUB body.

Features

• Revised 12-speed gradation for first-class efficiency and optimum acceleration in all situations
• Compatible with new HG L2 road 12-speed FREEHUB body

Product features

• Use: Gravel, Cyclocross
• Model: CS-R8100-12 / CS-HG710-12
• Type: Hyperglide L2 Road
• Gear ratios: 12-speed
• Recommended chain: 12-speed HG

Gradation (choose variant)

• 11-34 (11-12-13-14-15-17-19-21-24-27-30-34 teeth)
• 11-36 (11-12-13-14-15-17-19-21-24-28-32-36 teeth)

Material

• Pinion carrier: Aluminum
• Pinion: Steel
• Locking ring: steel

Weight

• approx. 345g/11-34 | 391g/11-36 (manufacturer information)

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Shimano CN-M8100 12-speed chain 126 links with Quick-Link

The special design of the Shimano CN-M8100 12-speed chain provides improved shifting performance and smoother running - even in rough terrain. The also new SM-CN910-12 Quick-Link closure allows for easy installation.

Features

• Special chain design for new drive components
• Better chain guide with a larger area at the end of the inner plate, which holds the tooth to the front and cassette sprocket
• Improved shifting performance
• Easy assembly
• Smoother ride even in rough terrain
• Compatible with the new generation of drivetrain components
• Comes with the user-friendly Quick-Link (SM-CN910-12)
• Quick-Link pliers for installation and removal (TL-CN10) - Not included!

Product features

• Use: MTB, Gravel, Cyclocross
• Model: CN-M8100
• Gear ratios front: 1/2-speed
• Shift stages rear: 12-speed
• Type: HG
• Hollow pin: No
• Outer plate coating: SIL-TEC
• Coating of the inner plate: Chromizing
• Closure: Quick-Link SM-CN910-12

Links

• 126

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Technologies

SEIS SHIMANO ELECTRONIC INTELLIGENT SYSTEM
The SEIS innovative shift technology is still based on the SHIMANO INDEX SYSTEM (SIS) that has proved its superior gear changing characteristics over the years. The big difference is that in this case, the shifting action is provided for by electronics instead of mechanics. This electronic shifting system has been extensively tested over past two years by several professional riders in all conditions possible, such as rain, mud, low temperatures, cobble stone roads and combinations of all of these at the same time. Shifting is executed by simply pressing the button. No power is needed to shift, which gives important advantages since it is easier now to always keep a tight grip on the handlebar and to keep your concentration on riding instead on shifting. The shift system allows accurate and effortless shifting in difficult circumstances like when you have cold hands or when you are completely exhausted. Furthermore, the shifting performance will never be affected by contaminated or stretched cables since the shifting signal is transferred electronically. The operating buttons work similarly to mechanical Dual Control Levers so you don’t need to re-program your mind for a new system.

E-Tube
E-Tube platform offers optimum flexibility on your bike. E-TUBE transmits interactive signals and power supply to each parts by “Plug & play” connection. E-TUBE is no rust, no stretch, no freeze and it ensures advanced low maintenance. And SM-PCE1 connects between PC and components to update firmware. Digital device stay the latest version with updating firmware for improve function.

Shimano Shadow RD+ 
Less distraction quiet drive train. Rear Derailleur Stabilizer reduces chain slap. Simple solution for chain drop. Lighter and more efficient than roller type chain device.

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Shimano GRX Di2

• Manufacturer number: GRXDI28252X121136170


Manufacturer:
SHIMANO INC.
3-77 Oimatsu-cho, Sakai-ku, Sakai-shi
590-8577 Osaka
Japan
https://www.shimano.com


Person responsible in the EU:
Shimano Europe BV
High Tech Campus 92
NL-5656 Eindhoven
Netherlands
[email protected]
https://www.shimano.com