Index Rear Derailleurs and set Front Derailleur limits using E-Tube Project
Learn how to set up your di2 front derailleur electrical limits and index or micro-adjust your di2 rear derailleur using E-Tube Project 4.
Rear Derailleur (1x)
GRX RD-RX817
If you've been looking at GRX Di2 components you may have seen that there are two rear deraileurs. This RD-RX817 and its lightweight cousin, the RD-RX815.
The RD-RX817 was developed by Shimano specifically for use in 1x bikes. This means that running this rear derailleur with a front derailleur is officially not supported. There are reports of users installing a front derailleur anyway, like this user on bikeforums.com. If you do, keep in mind that this is not Shimano approved and your shifting quality could suffer.
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This RD-RX817 has a total capacity of 31T, allowing you to run an 11-42T cassette. Its top sprocket max is 11T and the low sprocket max is 42T (min 40T).
Both GRX rear derailleurs feature a clutch mechanism, just like the Ultegra RD-RX805 and the mountain bike rear derailleurs. Shimano call this the chain stabiliser. It can be adjusted and prevents chain slapping (or worse, dropping your chain).
Specifications
- Model code
- RD-RX817
- Series
- GRX RX815
- Weight
- 318g
- SD50 ports
- 1
- Total capacity
- 31T
- Low sprocket max
- 42T
- Low sprocket min
- 40T
- Top sprocket max
- 11T
- Top sprocket min
- 11T
- Pulley teeth
- 11
- RD Type
- Shadow RD+
- Clutch
- Yes
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Installation Guide: RD-RX805 / RD-RX815 / RD-RX817 Di2 Rear Derailleur
Stuck installing your new Di2 rear derailleur? Read how to install the RD-RX805 / RD-RX815 / RD-RX817 Di2 rear derailleurs.
Understanding Di2 derailleur specifications
What is a rear derailleur's total capacity, really? Why is there a top sprocket minimum? And what about front derailleurs? Chain line, total capacity, Top gear teeth? This page explains all of those, and more.