Running 1x on a gravel bike used to mean piecing together road shifters, mountain derailleurs, and a workaround link to make everything talk to each other. Shimano's GRX-810 Mechanical 1x 11-Speed Kit collects the pieces that make the setup work as-designed — an ST-RX810 dual control lever, the RD-RX812 clutched rear derailleur rated to a 42T low cog, a Deore XT CS-M8000 cassette in 11-40T, and a CN-HG701 chain with Quick-Link. Everything is spec'd to work together out of the box, no adapters required.

The RD-RX812 is where the 1x story lives. It uses Shadow RD+ geometry to tuck the derailleur close to the frame, keeping it out of the way on tight singletrack and rock strikes, and pairs that with a gravel-tuned clutch that sits between road and mountain tension settings. There's an on/off switch for wheel removal or smoother-surface rides where the extra tension isn't needed. The 42T max low cog and 31T total capacity are sized for exactly the 11-40T cassette in this kit, so the chain sits right at both ends of the range without slack at the top or bind at the bottom.

The ST-RX810 right lever handles rear shifting and hydraulic actuation for the rear caliper. GRX hoods sit taller than Shimano's road hoods, with a raised head that gives you something to brace against on rough descents, plus textured coatings on the hoods and lever blades for grip in wet or dusty conditions. Since this is a 1x kit, only the right-side lever is included — the left brake lever, front rotor, calipers, crankset, bottom bracket, and rear rotor are sourced separately.