The Reserve 44 Zipp ZR1 ST Carbon Rear Wheel strikes the perfect balance between lightweight responsiveness and aerodynamic efficiency. With a 44 mm rim depth, this wheel is engineered for all-round performance — quick on the climbs, smooth on the flats, and composed through crosswinds. Combined with Zipp’s precision-built ZR1 hub and SRAM XDR compatibility, it delivers effortless power transfer and the kind of refined ride feel that defines Reserve’s reputation for real-world speed.

The 44 mm rim profile embodies Reserve’s all-conditions versatility. It’s deep enough to cut through the wind yet shallow enough to maintain control in unpredictable gusts. The carbon structure is hand-laid using Reserve’s proprietary lay-up for tuned stiffness, strength, and vibration damping. The aerodynamic shaping has been refined through CFD modeling and outdoor validation, producing consistent drag reduction across a wide range of yaw angles. Paired with a 21 mm internal width, the wheel is optimized for 25–32 mm tires, giving a stable, rounded tire shape that improves grip, comfort, and rolling efficiency across every mile.

At the core, Zipp’s ZR1 ST hub defines mechanical precision and reliability. Its German-engineered design uses fully sealed cartridge bearings for ultra-smooth, low-drag rotation in all conditions. The 66-point ratchet engagement system ensures near-instant power delivery when accelerating, sprinting, or climbing out of the saddle. The lightweight forged-aluminum shell and refined flange geometry distribute spoke tension evenly, improving lateral stiffness and power transfer. With the SRAM XDR freehub body, the interface is perfectly matched to modern 12-speed drivetrains, locking in efficiency and long-term dependability.

Each wheel is hand-built using Sapim CX-Ray bladed spokes in a two-cross lacing pattern for ideal strength-to-weight balance. The asymmetric spoke bed evens tension across the wheel, maintaining perfect alignment under load and preserving long-term trueness. The tubeless-ready, hookless rim design simplifies tire setup and allows lower pressures for improved traction, comfort, and rolling performance. The result is a wheel that feels fast in every environment — light on climbs, stable in crosswinds, and smooth on rolling terrain.

The Reserve 44 ZR1 ST rear wheel is for riders who want one wheel that can do it all: race, train, and conquer mixed-terrain roads with total confidence. It’s the perfect harmony of Reserve’s carbon mastery and Zipp’s mechanical precision — a combination that turns every watt into momentum you can feel. Light, aero, and endlessly capable, it’s not just a component — it’s an invitation to ride faster, farther, and smoother than ever before.