Wireless Di2 eliminated the junction boxes and routing headaches that made older electronic drivetrains a pain to install and maintain. The GRX ST-RX825 lever talks directly to the derailleurs over a wireless connection, which means the only thing running through your frame is brake hose. This left-side lever pairs with the BR-RX820 flat mount caliper and comes pre-bled with a 1000mm hose for front brake duty on 2x gravel setups.

Shimano shaped the hood body specifically for flared handlebars, which are standard equipment on gravel bikes at this point. The transition from bar to hood follows a rounder profile that increases the contact patch under your palms and reduces pressure points during long days in the saddle. Raised hoods and a ribbed surface texture add grip when you're out of the saddle on rough terrain, and an anti-slip coating on the aluminum brake lever blade keeps your fingers from sliding during hard braking efforts.

The third shift button sits on the inside of the hood where your thumb naturally rests, which is a GRX-specific placement that works well when you're riding in the drops on technical descents. All three buttons can be programmed through Shimano's E-Tube Project Cyclist app, and the FRONT SHIFT NEXT function lets you assign a single button to toggle between chainrings rather than dedicating separate buttons to upshift and downshift. That frees up a button for other tasks like scrolling through GPS screens or triggering a lap counter.... Read More