Shimano GRX RD-RX400 Rear Derailleur 2x10-Speed

What Is It?

The Shimano GRX RD-RX400 is a 10-speed rear derailleur designed for gravel cycling and mixed-terrain riding. Featuring Shimano SHADOW RD+ chain stabilisation technology, it helps reduce chain slap and chain drops on rough surfaces while delivering smooth, reliable shifting. It is designed for use with compatible Shimano 2x10-speed GRX drivetrain systems.

Key Features

• 10-speed drivetrain compatibility: Designed for Shimano GRX 2x10-speed setups.

• SHADOW RD+ technology: Integrated chain stabiliser helps reduce chain movement and chain drops.

• On/off stabiliser switch: Allows the chain stabiliser to be adjusted for different riding conditions.

• Gravel-specific design: Optimised for dependable shifting on mixed and uneven terrain.

• Wide gear range: Supports compatible cassettes with up to a 36-tooth largest sprocket.

• Precise shifting: Helps deliver consistent gear changes across road and gravel surfaces.

• Durable construction: Built for the demands of regular gravel and endurance riding.

Specifications

• Brand: Shimano

• Series: GRX

• Model: RD-RX400

• Product type: Rear derailleur

• Rear speeds: 10-speed

• Drivetrain configuration: 2x10-speed

• Compatible chain: Shimano HG-X 10-speed

• Maximum front chainring difference: 16T

• Total capacity: 41T

• Maximum low sprocket: 36T

• Minimum low sprocket: 32T

• Maximum top sprocket: 11T

• Minimum top sprocket: 11T

• Technology: Shimano SHADOW RD+

• Chain stabiliser: Adjustable, with on/off switch

• Mounting: Conventional direct attachment or compatible direct-mount configuration

• Average weight: 303g.

   

Benefits

• Reduces chain slap and improves drivetrain stability on rough terrain.

• Provides reliable shifting for mixed-surface adventures.

• Supports a wide range of gears for climbing and faster riding.

• Helps maintain a quieter drivetrain on gravel roads and trails.

• Offers dependable performance for long-distance cycling.

Best Suited For

Gravel cyclists, endurance riders and bikepackers using compatible Shimano GRX 2x10-speed drivetrains who want reliable shifting and improved chain stability on varied terrain.