Shimano GRX RD-RX820 2×12-speed Rear Derailleur

For your riding freedom: the Gravel GRX 2×12-speed Rear Derailleur RD-RX820 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, RX820 delivers top-tier performance without an over-the-top price.

For riders seeking the best of both worlds, the new 2×12 RX820 UNDROPPABLE drivetrain is the choice. Utilizing a gravel-optimized 48/31 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.

This setup delivers precise mechanical shifting both front and rear and an integrated SHADOW PLUS chain stabilization for ultimate security over bumpy terrain. The gravel-specific 2×12 option maintains tighter rear cassette gear steps, ideal for subtle cadence changes during competitive racing and spirited weekend group rides. And the 2×12 setup seamlessly interfaces with most existing 700c wheels thanks to its use of the tried-and-true HG freehub body design.

Features – Shimano GRX RD-RX820 2×12-speed Rear Derailleur

• Silent and uninterrupted rear shifting on rough terrain
• Adjustable chain stabilizer prevents chain slapping and drops
• SHIMANO SHADOW RD+
• Smooth and reliable mixed surface shifting
• Toggle clutch ON/OFF to match the terrain
• Switch stabilizer ON/OFF to match the terrain
• Gravel-tuned clutch tension
• Compatible with current road DUAL CONTROL LEVER

Product features

• Use: Gravel, Cyclocross
• Group: GRX
• Model: RD-RX820
• 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: 42T

Material

• Aluminum
• Steel
• GFRP

Color

• Series color

Weight

• approx. 270g (manufacturer information)

Scope of delivery

• 1 x Shimano GRX 2×12-speed RD-RX820 Rear Derailleur

Technology

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.

Shimano GRX 12-speed