Shimano GRX FD-RX815 Di2 Front Derailleur – 11-Speed, Down Swing, Braze-On
The Shimano GRX FD-RX815 Di2 Front Derailleur is purpose-built for gravel and adventure cycling,
delivering smooth, reliable electronic shifting across mixed terrain. Designed for 2x GRX Di2
drivetrains, this front derailleur features a down-swing, braze-on design with optimized geometry
for wider tire clearance. Engineered to accommodate chainstay angles of 61–66° and top gears of
46–50T, it ensures precise, consistent shifts for 11-speed drivetrains in rugged conditions.
Why you’ll like it
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GRX-specific design – engineered for gravel and adventure performance.
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Di2 electronic shifting – delivers precise, reliable shifts at the push of a button.
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Braze-on mount – lightweight and clean installation.
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Down-swing configuration – optimized for frame compatibility and wide tire clearance.
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Supports 46–50T top gear – ideal for gravel and endurance gearing setups.
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Chainline: 46 mm – designed to match GRX 2x drivetrains.
What’s in the box
- 1 × Shimano GRX FD-RX815 Di2 Front Derailleur (braze-on, down swing)
Tech specs
| Manufacturer |
Shimano |
| Series |
GRX |
| Model |
FD-RX815 |
| Manufacturer Part # |
KFDRX815F |
| Speed |
11-speed (front) |
| Mount Type |
Braze-on |
| Configuration |
Down swing |
| Chainstay Angle |
61–66° |
| Top Gear Capacity |
46–50T |
| Chainline |
46 mm |
| Application |
Gravel / Adventure / Endurance road (Di2 electronic) |
Fit notes
- Designed for Shimano GRX Di2 2x 11-speed drivetrains.
- Requires Di2 wiring and shifters (sold separately).
- Braze-on mount; an adapter may be required for clamp-style frames.
- Compatible with top gear chainrings between 46–50T.