Quick answer: Shimano's new Dura-Ace R9370 C50 is built around two changes: a fully serviceable cup-and-cone bearing system, and newly engineered carbon spokes with purpose-built lacing. Rather than chasing one metric, Shimano is targeting a balance of weight, aerodynamics and stiffness with a 50mm-depth carbon disc wheelset built for all-round race versatility and tubeless-ready.
What’s new?
The R9300 generation is a full rebuild of Shimano's top-tier road wheel platform, landing alongside Shimano's new pedal, cleat and shoe range, with two headline changes that both affect how the wheel performs, not just how it's made:
- Cup-and-cone bearings, fully serviceable. Instead of a sealed cartridge bearing you replace as a unit, the new hubs use an angular-contact cup-and-cone design that can be adjusted and serviced rather than swapped out.
- Newly engineered carbon spokes. Shimano describes the spoke and lacing choices as structural decisions, not aesthetic ones, they're tuned to influence lateral stiffness, acceleration and how directly your power converts into forward motion.
Cup-and-cone bearings, explained
Cup-and-cone bearings work on precisely machined races - the cup sits in the hub body, the cone on the axle - with the bearing preload set and secured by hand rather than locked at manufacture. The practical benefit is longevity: worn components can be refreshed individually rather than requiring a full hub or wheel replacement, which is the main way this design differs from a sealed cartridge bearing. Shimano has added replaceable bearing cups and upgraded waterproof sealing for this generation specifically, aimed at keeping performance consistent as conditions get wet or gritty. The system is engineered to manage both lateral and vertical loads at once - the combined forces you put through a wheel when sprinting, cornering, descending and braking, not just rolling in a straight line.
Carbon spokes and lacing
The R9300 generation introduces newly engineered carbon spokes paired with purpose-built lacing, using mixed-diameter spokes to balance weight against structural rigidity. Shimano's position is that spoke choice is a stiffness and power-transfer decision as much as a weight one, how efficiently the wheel resists flex under load has a direct effect on how much of your effort becomes forward motion.
Dura-Ace R9370 C50: the specs
The C50 is a 50mm-depth carbon disc wheelset built for race versatility across flat and rolling terrain.
- Rim depth: 50mm, carbon, hooked construction
- Weight: 593g front / 709g rear
- Spokes: 21 per wheel, straight-pull, bladed carbon
- Wheel size: 700c, tubeless-ready
- Axle: 12mm E-THRU, front and rear
- Brake type: Centre Lock disc
- Rim width: 31mm external (front) / 32mm external (rear), 23mm internal
FAQ
What makes cup-and-cone bearings different from cartridge bearings?
Cartridge bearings are sealed units you replace as a whole when they wear out. Cup-and-cone bearings run on machined races that can be adjusted for preload and serviced individually, so worn components can be refreshed rather than requiring a full hub replacement, at the cost of needing occasional adjustment rather than being fully sealed and forgotten.
Is the Dura-Ace R9370 C50 tubeless-ready?
Yes.
What terrain is the Dura-Ace R9370 C50 built for?
It's positioned as an all-rounder, a 50mm depth that balances aerodynamics, weight and stiffness for flat and rolling race terrain, rather than being a specialist climbing or time-trial wheel.
Is the Dura-Ace R9370 C50 disc-brake only?
Yes, it uses a Centre Lock disc brake interface with 12mm E-THRU axles front and rear.