With an integrated chain stabilizer mechanism, the GRX rear derailleur provides a quieter experience and shifting security and precision on mixed terrain. For rides on smooth surfaces, the derailleur features an on/off switch for the chain tensioner. The RD-RX820 rear derailleur is compatible with MTB cassettes with a 42T low sprocket max. GRX 12 speed rear derailleur for double cranks
Adjustable chain stabilizer prevents chain slapping and drops
Gravel-tuned clutch tension can be toggled ON/OFF to match the terrain
Maximum front difference: 17T
Total capacity: 42T
Low sprocket: Max. 34T/Min. 30T
Top sprocket: 11T
Attributes
Max Front Difference
17T
Maximum Cog
34T
Minimum Cog
11T
Primary Color
Grey
Cage
GS
RD Capacity
42T
RD Spring Type
Shadow Plus
Speed
12
Mount
Standard
