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GRX RD-RX815 11-Speed Di2 Rear Derailleur

Mfg PartNum:IRDRX815
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Backorder: This item is currently out of stock but is available to purchase today as a backorder. The expected availability date shown above is our best estimate as to when it will be shipped to you, but this date is subject to change based on our receipt of this item from its vendor. Shipping in the continental US is free for all backorder items (for international orders, our customer service team will contact you when the item is available to ship). Your credit card will not be charged until your item ships (Paypal requires payment up front, but you can cancel for full refund). Anytime prior to shipment, your backorder can be cancelled by contacting our customer service team.

GRX RD-RX815 11-Speed Di2 Rear Derailleur

The Shimano GRX 11-Speed Di2 rear derailleur brings mountain bike technology to gravel riding with a clutch equipped rear derailleur allowing smooth shifting on rough terrain. The Shadow RD Technology utilizes it's race-proven, low-profile design to offer a derailleur that is more compact and fits closer to the frame, ensuring less damage in a crash. With the adjustable chain stabilizer, chain slapping and dropping are prevented while the gravel-tuned clutch tension provides silent and uninterrupted electronic rear shifting on the roughest terrain.


  • Operates with Shimano Di2 for digital electronic shifting
  • Toggle clutch ON/OFF to match the terrain
  • Gravel-tuned clutch tension provides smooth and reliable mixed surface shifting
  • Switch stabilizer ON/OFF to match the terrain
  • For 1x and 2x drivetrains

B-Stock - This product has one or more B-Stock units available. These units can be purchased at a discount (see option select). B-Stock units were returned from other customers and may have missing or damaged packaging materials. These units are otherwise as new. The full manufacturer warranty applies. Click Here for more information.

The product weight specified is an approximate weight based on the manufacturer's specifications (if available) or our measurement of one or two examples. For most products, the weight will typically vary by 5% to 10%.


Mfg PartNum: RD-RX815 




Total Capacity: 38T 


Max. front difference: 17T 


Top sprocket: 11T/Min. 11T 


Low sprocket: Max. 34T/Min. 30T 


Rear Speeds: 11 


Top-Normal Spring Type: SHADOW RD plus 


Weight: 287 g 

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