Shimano GRX RX880 Disc Brake Wheel Rear

Shimano GRX RX880 Disc Brake Wheel Rear is a carbon gravel wheel built around a shallow 32mm rim, designed for riders who want a wheel that climbs efficiently and holds its line when the wind picks up on exposed gravel roads. It's sold individually as the rear half of the WH-RX880 wheelset, Shimano's top-tier GRX wheel, and at $1,010 it's priced in line with that position — a carbon rim, a reworked hub, and swappable freehub bodies aimed at riders who run more than one drivetrain setup or want one wheel to cover racing and long-distance riding. GRX is Shimano's gravel-specific groupset line, and this wheel is built to match it — the same Center Lock rotor mount, thru-axle spacing, and freehub options found across the rest of the GRX disc brake range.

The rim is carbon, hooked rather than hookless, with a 25mm internal width and a 30.7mm external width that supports tire widths from 32mm up to 50mm. That range covers everything from a fast gravel racing tire to a wider adventure or bikepacking tire without changing wheels. The 32mm rim depth is shallow by design; Shimano built it that way to keep the wheel composed in crosswinds and to shave rotational weight for long climbs on loose or broken terrain, rather than chasing the aerodynamic gains of a deeper road rim. This rear wheel weighs 762 grams on its own, which is light for a wheel rated to 50mm tires and Center Lock disc brakes. The rim comes tubeless ready, with tape and valve cores installed at the factory, so it's set up to run sealant straight out of the box rather than needing a separate tubeless conversion kit. The hooked rim bead also means a broader range of tires seat reliably on it compared to a hookless design, which matters if this wheel ends up paired with tires from more than one brand over its life.

Twenty-four bladed, butted stainless steel spokes tie the rim to Shimano's hub, which uses Direct Engagement technology carried over from Shimano's Dura-Ace road wheels. The design is meant to add rigidity to the wheel and speed up engagement when you put power down, which matters most coming out of a loose corner or restarting on a climb after a gravel section forces a slowdown. The hub bearings are cup-and-cone rather than sealed cartridge bearings, a deliberate choice that keeps the wheel serviceable and adjustable in the field rather than requiring a full bearing swap when it's time for maintenance — a detail that matters more the further this wheel gets from a bike shop. The rear hub runs a 12mm E-THRU thru-axle with 142mm spacing, the standard fitment on nearly all modern disc-brake gravel frames, and the brake rotor mounts via Center Lock, matching the rest of the GRX disc brake lineup.

Where this wheel stands apart is freehub flexibility. Shimano offers the WH-RX880 rear with either an HG L2 freehub body, compatible with 12-speed cassettes from 11-30T up to 11-36T, or a MICRO SPLINE freehub body, compatible with 12-speed cassettes from 9-45T up to 10-51T. That's a meaningful choice for gravel riders specifically, since it means the same wheel can run a tighter, road-style cassette for fast group rides and racing, or a wide-range MICRO SPLINE cassette built for loaded touring and steep, sustained climbing, depending on which body is fitted at the factory. It's worth confirming which freehub body is included before ordering, since the two options aren't interchangeable without swapping the body itself, and they're matched to different GRX drivetrain builds.

Shimano built the RX880 for fast riding and long climbs on uneven terrain, and the spec sheet backs up that claim: a light carbon rim shaped for crosswind stability, a hub built for quick engagement out of loose corners, and a freehub system flexible enough to match different gearing needs as a rider's goals change. It's a rear wheel for someone who's serious about one gravel bike doing double duty — racing one weekend, loaded touring or long climbing days the next — rather than a wheel built around a single narrow use case. Paired with the matching RX880 front wheel, it rounds out a wheelset built specifically around Shimano's GRX gravel groupset, and it swaps onto most existing GRX-equipped bikes without changing anything else on the build.