Shadow Rear Derailleur+ 2x

The Shimano RD-RX815 GRX rear derailleur is Shimano's first GRX Di2 rear derailleur. The 815 in the model name indicates that this is the 2x medium-cage version of the GRX rear derailleur. It utilizes an adjustable chain stabilizer to prevent chain slapping and drops.

The RD-RX815 can be used with or without front derailleur. It's GRX sibling, the RD-RX817 can not be used with a front derailleur.

Like other Shimano clutch derailleurs it has an ON/OFF switch that lets you switch the clutch on or off.

This rear derailleurs ensures silent and uninterrupted rear shifting on rough terrain, smooth and reliable mixed surface shifting.

It is compatible with any current road dual control lever and of course the GRX specific dual control levers.

Top sprocket: Max. 11T/Min. 11T
Low sprocket: Max. 34T/Min. 30T
Total capacity: 38T

RD-RX815 Shadow RD+

Details & specifications

Shimano model codeRD-RX815
Shimano model nameShadow Rear Derailleur+ (short cage)
Weight0 g
SeriesGRX Di2
Downloads Di2 Rear derailleur manual
GRX manual
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Shopping links

Are you looking to upgrade your bike using this component? We've added shoppings links to this component's Amazon and eBay pages. Click the images below to view the Amazon product page or eBay search results.

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Installation guide

Read how to install and set up this rear derailleur in our RD-RX805 / RD-RX815 / RD-RX817 rear derailleur installation guide.

GRX rear derailleur