Zipp 303 S Carbon Tubeless Rear Bicycle Wheel

The Zipp 303 S Carbon Rear Wheel is a tubeless-ready road wheel built for riders who want the aerodynamic benefit of a deep-section carbon rim without the price of Zipp's flagship 303 Firecrest line. It carries a 45mm rim depth and 27mm width (23mm internal), a rim shape borrowed directly from the Firecrest design and tuned to optimize tire profile at lower pressures. Running wider tires at lower pressure reduces rolling resistance and takes the edge off road vibration, which matters most on long endurance rides and mixed-surface routes.

This listing is the rear wheel only, built around a 176D hub with a Center-Lock disc mount and a 12mm thru-axle at 142mm spacing — the axle standard on nearly every current disc-brake road and gravel frame. The rim is UD carbon and hookless, so it's compatible with tubeless tires exclusively; standard clincher tires with tubes are not supported. The freehub body is set up for SRAM 10 or 11-speed cassettes, making this a direct fit for SRAM-equipped bikes looking for a carbon upgrade over stock alloy wheels.

Who It's For

• Riders on SRAM 10- or 11-speed drivetrains upgrading from an aluminum wheel to carbon
• Riders who want tubeless tire compatibility for lower rolling resistance and better flat protection
• Riders with disc-brake frames using 12x142mm thru-axles and Center-Lock rotors
• Consider a different wheel if you run rim brakes, a Shimano or Campagnolo freehub, or need a front wheel — this listing covers the rear wheel only

What to Look For

• Confirm your frame's rear axle is 12x142mm thru-axle with Center-Lock disc mounts before ordering
• The rim is hookless, so you're committed to tubeless-specific tires — check your current tires' tubeless compatibility first
• Match the freehub to your drivetrain: this wheel is built for SRAM 10/11-speed only

Key Features

Rim: The UD Carbon Hookless Rim runs a 45mm depth and 23mm internal / 27mm external width, adapted from the 303 Firecrest. That shape lets you run wider tires at lower pressure, which lowers rolling resistance and improves ride comfort on rough pavement.

Hub: A 176D hub with a Center-Lock disc mount and smooth matte finish, set up with a Presta valve for tubeless setup.

Tire compatibility: Listed as Tubeless Ready with a hookless bead, this wheel takes tubeless tires only — tube-type clinchers are not compatible.

Freehub: Built for SRAM 10/11-speed cassettes, making it a direct swap for SRAM-equipped disc-brake road or gravel bikes.

Rider Intent Summary

• Biggest strength: 303 Firecrest-derived rim shape (45mm depth, tubeless-ready) at a more accessible price point
• Tradeoff: hookless rim limits tire choice to tubeless-specific tires; sold as a rear wheel only with a SRAM-only freehub
• What makes it different: brings Zipp's higher-tier aero rim design down to a wheel built around a 176D hub and Center-Lock disc mount

Victory's Take

We see the 303 S as a smart entry point into Zipp's aero rim technology for SRAM riders who want the 303 Firecrest's rim shape without the Firecrest price. At Victory Bicycle Studio, we'd pair it with a quality tubeless tire from the start to get the ride quality this rim is designed for.