What is the difference between RD-RX812 and RD-RX810?

RD-RX812 is the 1x variant (42T max cassette, 31T capacity) for single chainring setups. RD-RX810 is the 2x variant (34T max cassette, 40T capacity) for double chainring setups. Choose based on your intended front drivetrain configuration.

Does the RD-RX812 work with road shifters?

Yes — it is compatible with current Shimano 11-speed road Dual Control Levers (STI) such as ST-R7000, ST-R8000, and ST-R9100. You do not need separate mountain bike shifters.

Can I run an 11-46T cassette with this derailleur?

No — maximum cassette is 42T. For 11-46T or larger, you would need a Shimano MTB derailleur (such as RD-M8000) with appropriate chain and shifter compatibility changes.

Shimano

Shimano GRX Rear Derailleur, RD-RX812, 1x11-Speed (Upto 42T CasSette)

Name: Shimano GRX Rear Derailleur, RD-RX812, 1x11-Speed (Upto 42T CasSette)
Brand: Shimano
SKU: CMB_WOW_IRDRX812
Price: 9560.00 INR
Availability: InStock
Author: InstaSport Editorial

₹9560.00

Description

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