Shimano offset the GRX chainline 2.5mm outboard for a reason: gravel bikes need room for bigger tires and the mud that sticks to them. The FD-RX825 front derailleur carries that wider chainline into the Di2 world, giving you electronic shifting precision without sacrificing the clearance that makes GRX work on mixed terrain. If you're building up a 2x12 gravel bike with Di2 or upgrading from the mechanical RX820 system, this is the front derailleur that completes the picture.

The semi-wireless Di2 architecture keeps the cockpit clean. Your ST-RX825 shifters communicate wirelessly with the derailleurs, so there's no junction box to hide and no extra wires running through the handlebars. The front derailleur connects to the system via a single SD300 wire that runs from the battery through the frame. Setup is straightforward, and once everything's paired through E-Tube Project, the system handles itself.

Shimano designed the FD-RX825 with a 17-tooth capacity, which covers the 48/31T rings on the FC-RX820 crankset and the 46/30T rings on the FC-RX610. That range lands you squarely in gravel territory—low enough gearing to spin up loose climbs, high enough to keep up on pavement sections without cross-chaining into oblivion. The cage geometry manages the chain through shifts even when you're putting down power, which matters when you're trying to drop into the small ring mid-climb on a gravel pitch.... Read More