Shimano GRX RD-RX820 12-Speed Rear Derailleur
Power Meter City May 29, 2025MPN: IRDRX820
$145.00
A feature packed Shimano GRX 12-speed mechanical rear derailleur
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Shimano GRX RD-RX820 12-Speed Rear Derailleur
The Shimano GRX RD-RX820 12-Speed Rear Derailleur packs the best features found in Shimano’s GRX 12-speed Di2 rear derailleur into a more affordable mechanical version. It has sealed bearings for additional protection against the elements and is available in a single cage length. This means you can easily change cassettes and gear ratios based on the terrain you are riding. The GRX RD-RX820 rear derailleur is compatible with 11-34T and 11-36T cassettes.
Additionally, this derailleur is made to be dependable on mixed terrain. It features SHADOW RD+ and a stabilizer switch. Both of these features help ensure reliable shifting on rough surfaces. SHADOW RD+ minimizes chain slap and noise from your drivetrain while the stabilizer switch provides additional chain tension for bumpy and rough terrain. The stabilizer switch can also easily be moved between ON and OFF based on the type of surface you are riding on.
Technology
Shimano’s SHADOW RD+
SHADOW RD+ helps minimize drivetrain noise while improving shift quality on rough terrain. The chain stabilizer system helps improve chain tension so you can shift gears regardless of terrain.
Stabilizer Switch
Easily move this switch ON or OFF based on your terrain. For rough surfaces, turn the stabilizer ON to keep shifting crisp and reduce the chances of damaging your derailleur.
Other Versions to Consider
Shimano GRX RX825 12-Speed Di2: We also carry the Shimano GRX RD-RX825 Di2 12-Speed Rear Derailleur. We recommend this to riders who are looking for a Di2 12-speed version.
Compatibility
- Drivetrain: Compatible with Shimano GRX 12-speed mechanical drivetrains.
- Cassette: Works with 11-34T and 11-36T cassettes.
Shimano GRX RD-RX820 Rear Derailleur Specs
- Speed: 12-speed
- Color: Black
- Weight: 270 grams
Q&A
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