Electrifying Shimano’s 12-speed gravel component family, the new 2 x 12-speed GRX RX825 Di2 components combine Shimano’s unrivaled electronic shifting with optimized gearing options for riding, racing, and all-day adventures. The new suite of electronic Di2 parts features dual control levers refined for comfort and control, a SHIMANO SHADOW RD+ equipped rear derailleur for better chain management, and a gravel-optimized front derailleur for precise shifting. 

Designed for gravel riders who live to be in the moment, who venture down lonely, unknown dirt roads, who take on routes and races with unpredictable outcomes, Shimano GRX 12-speed Di2 delivers precise, reliable, distraction-free performance in all conditions.

• Evolved Di2 Platform – Redesigned Di2 system with fast, precise shifting and a wireless cockpit design for the ultimate performance and absolute reliability.
• Advanced Gravel Drivetrain – Optimized 12-speed gearing for unrivaled efficiency and Shimano’s proven HYPERGLIDE+ technology for seamless shifting, no matter the situation.
• Refined Interface and Ergonomics – The ultimate balance of comfort and grip, GRX offers unparalleled ergonomics, a cleaner cockpit design, and ultimate customization.

Electrified 2 x 12-Speed GRX Gearing Options

Shimano’s new suite of gravel components brings an electronic shifting option to the 2 x 12 GRX group that launched last year. Pairing the new GRX RX825 Di2 shift levers, available satellite switches, front derailleur, and rear derailleur with existing RX820 crankset, cassette, and brakes, riders will enjoy Shimano’s hallmark Di2 shifting performance and reliability with 2 x 12-speed gravel gearing.
Like with the RX820 mechanical components, riders can tailor their gearing with the 48/31-tooth chainrings or opt 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 tight gear steps so they can spin a comfortable cadence.

Unrivaled Shimano Di2 Electronic Shifting for Gravel

Like its 12-speed DURA-ACE, ULTEGRA, and SHIMANO 105 Di2 siblings, the new GRX Di2 system is wired where it makes sense, featuring a central, multi-port battery that supplies stable, long-lasting power to both front and rear derailleurs. Smaller diameter wires connect directly from the battery to each derailleur, eliminating the need for junctions and streamlining the build process. The central internal battery also simplifies charging and remains secure over the roughest roads, trails, or whatever less travelled path a rider may choose.

Shimano Di2 Wireless Cockpit

Shimano’s 12-speed GRX Di2 features a wireless gravel-specific cockpit where raised hoods with ribbed surface texture and anti-slip brake levers provide ultimate hand security no matter how spicy the ride gets. That secure hand position is enhanced, as it was with the original GRX RX815 Di2 DUAL CONTROL LEVERS, with the location of the third Di2 button on the inside of the hood.

Whether used as another shift location or for scrolling through screens on a cycle computer, this third button is another way to fully experience Shimano’s electronic Di2 system.

Flared For Gravel

The new dual control levers also employ a gravel-optimized body shape cross-section for seamless integration with flared handlebars. Rounder in shape, the transfer from handlebar to hood is smoother and creates a larger surface area to help eliminate pressure points.

ST-RX825 - Hydraulic Disc Brake DUAL CONTROL Lever

• Wireless Di2 Connectivity
• 2 x 12-Speed Dual-Control Lever
• Gravel-specific brake lever and bracket ergonomics
• New flared drop bar optimization
• Anti-slip coating on brake lever surface
• Three Di2 buttons per lever for E-TUBE PROJECT Cyclist app customization
• Replaceable coin cell batteries (2 x CR1632) with expected lifespan of 3.5 to 4 years
• Weight: 415 grams/pair

Accessory Di2 Shift Switches

The new Di2 system also allows for accessory shift buttons, another key advantage of electronic shifting. Plugging in one of Shimano’s satellite shifters, whether on the tops, drops, or on aero bars, riders can more consistently maintain their effort without the need to move their hands. Like the third button on the GRX Di2 dual-control levers, these satellite switches can be assigned various functions including shifting of either derailleur, to control compatible lights and cycle computers, or as a lap button during workouts.

SHIMANO SHADOW RD+ Rear Derailleur

The RX825 rear derailleur features Shimano’s pioneering Shadow RD+ technology. With its convenient on/off switch, Shadow RD+ makes removing the rear wheel easy when turned off. When on, the drivetrain is under additional tension that makes for a quieter ride and more precise shifting.

Like on Shimano’s road 12-speed Di2 systems, the rear derailleur is also the communication hub of the drivetrain, communicating wirelessly with the shift levers, compatible cycle computers, and E-TUBE PROJECT Cyclist via a smartphone. It also houses the system’s charge port and the multi-function button which allows riders to easily check battery level, pair via Bluetooth, and enter adjustment mode for both derailleurs.

RD-RX825 Rear Derailleur

• SHIMANO SHADOW RD+ Chain Stabilization
• Integrated D-FLY Connectivity and Charging
• 12-speed
• Compatible with 11-34T and 11-36T cassettes
• Weight: 310 grams

Wider Chainline for More Clearance

Like the very first GRX groups, the RX825 system employs a wider, +2.5mm chainline for improved tire clearance. This is especially helpful with the trend towards wider tires and events where mud is expected.

FD-RX825 Front Derailleur

• Chainline +2.5mm vs. conventional road FD
• Wider tire clearance
• 2 x 12-speed
• Weight: 142 grams

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