The Shimano GRX 815 Di2 11-Speed Rear Derailleur has been specifically engineered for rough tracks, gravel roads and surfaces that would ordinarily cause the chain to bounce and slap. An innovative adjustable stabiliser uses spring force and friction to maintain tension through the chain, which prevents it from dropping and reducing noise from the drivetrain. The upshot is smoother, more reliable shifting no matter the surface, so whether you are riding bumpy gravel or smooth tarmac the derailleur functions with predictable crispness. You can even incorporate this into your regular electronic road-riding setup because the derailleur is compatible with current road Dual Control Levers.
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2 questions answered
Hi there, Yes, the GRX RD-RX815 Di2 is compatible with your Ultegra R8050 11-speed Di2 system and can replace the R8050 rear derailleur. It adds a clutch and handles wider cassette ranges for gravel use. Many thanks Joe W
Hi Nickos, Yes. The GRX RD-RX815 is 11-speed Di2 and runs on the same E-tube system as your Ultegra R8050, so it drops into your existing Di2 setup. The main difference is the GRX adds a clutch to keep the chain settled on rougher roads, and it handles cassettes up to 11-34T. Just update the firmware through E-tube after fitting so all the components match. Thanks
From a single Osaka workshop in 1921, Shimano has grown into the world's most influential component maker. The brand's relentless engineering — Dura-Ace, Ultegra, GRX, XTR — has shaped the way the world shifts, brakes and rides, on the road and off it.
Shimano's flagship groupset, Dura-Ace, has been the benchmark for top-level road components for more than five decades. Every refinement that lands on Dura-Ace eventually shapes the entire Shimano range, all the way down to entry-level drivetrains.
