Shimano has announced the launch of top-level Dura-Ace WH-R9370 wheels with the promise of “improvements in weight reduction, aerodynamic efficiency, and structural stiffness” – and the launch has a lot of people thinking that a complete new Dura-Ace groupset isn’t far away.
Lighter, stiffer and more aero? Full house! Those are the big three claims we see most frequently when high-performance bike products are launched, so Shimano seems to be following the script to some extent. Let’s hear what it has to say about the new wheels.
The WH-R9370 lineup comprises the C36, C50, C60 wheelsets – aimed primarily at road racing – and the C99 front wheel and the Rear Disc – designed for time trials and triathlon. The wheels are said to be optimised for 28-30mm tyres. Shimano is also sticking with cup-and-cone bearings.
> Cartridge vs. cup-and-cone bearings: Everything you need to know
Weights are down
One of the key advantages that Shimano promises with the WH-R9370 range is a lower weight to provide “a markedly more agile climbing feel and sharper acceleration—without sacrificing handling stability or durability”.
It claims these wheelset weights:
- C36: 1,170g (180g lower than previously)
- C50: 1,302g (159g lower than previously)
- C60: 1,609g (220g lower than previously)
How has Shimano lost the weight?
“This advancement stems from a fully re-engineered structure, highlighted by new carbon spoke technology, improved rim layups, and holistic system engineering across the rim, hub, and spoke architectures,” it says.
Aero optimised for 28-30mm tyres
We all know that riders are generally shifting towards wider tyres these days – racers included – and Shimano has recognised this with a shift to a 23mm internal rim width, which is 2mm wider than previously (many other brands already use a 23mm internal width, of course).
It says that external widths have been “engineered to balance aerodynamics and crosswind stability”.
“In controlled testing at 48km/h [29.8mph] on 30mm tyres, riders can achieve up to 2.7 watts less aerodynamic drag, combined with an overall weight reduction versus the previous generation, resulting in measurable gains in competitive scenarios,” says Shimano.
“Each rim profile was refined using advanced computational simulations and validated in controlled aerodynamic testing environments to ensure performance across real-world yaw conditions, not just idealised wind-tunnel angles.”
Shimano hasn’t released figures comparing the aero performance of WH-R9370 wheels with that of models from other brands.
Carbon spokes
One of the biggest changes with the launch of the WH-R9370 wheels is a shift from stainless steel to carbon spokes, which is something that ever more brands are doing with their high-end models. Shimano uses Aero (4.0mm x 1.1mm) spokes on the C36, C50 and C60, Super Aero (5.2mm × 0.8mm) on the C99. In many cases, it uses fewer spokes than previously,
“Spoke type, count, and configuration are tailored per model to deliver the intended ride character, whether lightweight climbing response, all-round race balance, or high-speed rigidity for sprinting and flat stages,” it says.
Upgraded cup-and-cone bearings
While most wheel brands use sealed cartridge bearings, Shimano is sticking with cup-and-cone, albeit in an updated format.
It says, “The new Dura-Ace wheels retain Shimano’s adjustable cup-and-cone hub architecture, known for its smooth rotation and precise adjustment characteristics. This system allows rotational torque to be optimised when installed on the bike, while maintaining stable performance under loads applied from multiple directions.
“In addition, the system has been evolved with replaceable bearings, improving serviceability and supporting consistent long-term performance. In comparative testing, Shimano’s updated cup-and-cone system demonstrates significantly lower friction than typical cartridge-bearing setups, contributing to smoother rolling and stable performance over time.
“Testing involved two wheels, one with cartridge bearings and one with a cup-and-cone system, to which identical levels of force were applied: 500N vertical force, representing the weight of the bike and the rider, 200N thrust force from pedalling, and 5,000N clamping force by the thru axle. The outcome showed a 30% lower rotational torque for the new cup-and-cone bearings, compared to typical cartridge bearings.”
Shimano hasn’t shared details of those “typical cartridge bearings”; there are many, many different options out there.
The fact that the new Dura-Ace wheels come with replaceable bearing cups is interesting; in the past, bearing cups have been machined directly into the aluminium hub shell.
Here’s the new Dura-Ace WH-R9370 lineup
WH-R9370-C36-TL
Price £1,099.99 front, £1,199.99 rear
Shimano’s description “Lightweight for climbing”
Internal width 23mm
External width 29.4mm
Spokes Aero, 18 front, 21 rear
Claimed weight 1,170g
WH-R9370-C50-TL
Price £1,099.99 front, £1,199.99 rear
Shimano’s description “Broad performance window for all-round riding”
Internal width 23mm
External width 31mm front, 32mm rear
Spokes Aero, 21 front and rear
Claimed weight 1,302g
WH-R9370-C60-TL
Price £1,099.99 front, £1,199.99 rear
Shimano’s description “Aerodynamic and with high stiffness”
Internal width 23mm
External width 31.5mm front, 32.3mm rear
Spokes Aero, 21 front, 24 rear
Claimed weight 1,389g
WH-R9370-C99-TL-F
Price £1,199.99
Shimano’s description “Dedicated time trial and triathlon front wheel”
Internal width 23mm
External width 35.2mm
Spokes Super Aero, 16
Claimed weight 792g
WH-R9370-D-TL-R
Price £2,299.99
Shimano’s description “Rear disc for maximum aero efficiency”
Internal width 23mm
Spokes Full disc construction
Claimed weight 987g
Is a new Shimano Dura-Ace groupset around the corner?
Dura-Ace is Shimano’s top-level road groupset and all the signs suggest a new version is on the way.
For a start, it’s about due. The latest versions of Dura-Ace were launched back in 2021.
Five years is a long time in bike tech. SRAM launched an updated version of Red in 2024 and Campagnolo unveiled an overhauled Super Record last year. It’s Shimano’s turn.
Beyond that, though, these new Dura-Ace wheels are R9370 series. Shimano released R9000 in 2012, R9100 in 2016 and R9200 in 2021. Following that naming convention, R9300 (and its subsets) should be along next. The wheels are the first R9300 products to be officially announced.
> Read our review of the existing Shimano Dura-Ace R9200 groupset
When can we expect the full groupset to be launched? We don’t know (and if we did, the information would be embargoed and we wouldn’t be able to say). We would guess soon, but not that soon.
Shimano unveiled the latest versions of Dura-Ace and second-tier Ultegra on 31 August 2021, so late-summer launches are perfectly possible.
On the other hand, early next year seems more likely to us. Manufacturers usually try to get their new products out in time for the Tour de France – cycling’s biggest shop window – and we’ve seen no new Dura-Ace shifters, derailleurs or chainsets used by the pros this year, which makes us think that we’re still a few months away, but we could be completely wrong. What do you reckon?
