Shimano has launched an updated range of Dura-Ace wheels today, as well as two brand new wheels.
In doing so, the Japanese giant has ended months of speculation around prototypes which have been used in WorldTour races.
The whole Dura-Ace wheel series has been updated, and two new wheels have been launched: the C99 front wheel, and a new rear disc.
The new series will carry the Shimano model code of WH-R9370, a number we saw on wheels fitted to Alpecin-Premier Tech's Canyon Aeroad bikes at the Tour de France earlier this month.
Although it probably won't have been on many riders' minds for a while, this almost certainly marks the end of the road for Dura-Ace tubular wheels too. The outgoing R9200 Dura-Ace models were available in tubular versions, but the new R9370 will be tubeless clincher only. Let's wait and see what Van der Poel uses come the cyclo-cross season.
A key question riders may ask is whether these wheels are hooked or hookless; there is no specific mention of this detail in the Shimano press release, but we assume the wheels are hooked as the price list mentions 'clincher, tubeless'.
We now have new Dura-Ace wheels, but this launch only adds fuel to the fire regarding when we will finally see a new Dura-Ace groupset released. Alongside the wheels, we also spotted new prototype Dura-Ace pedals at Paris-Roubaix this year, but remain in the dark regarding an official launch of a complete groupset.
We took the opportunity at the Tour de France grand depart to ask a Shimano big cheese the question, but unsurprisingly, received no new information.
The new R9370 wheels
Shimano says the new wheels are "engineered for modern racing in collaboration with WorldTour cyclists and pro triathletes." They are said to have been developed using Shimano’s ‘Science of Speed’ philosophy, though the brand hasn't gone into detail on what that is.
The new range still contains the familiar C36, C50 and C60 models, but now a super-deep C99 front wheel and rear disc wheel have also been added to the range. Until now, Shimano has not officially manufactured a disc wheel.
Weight has been trimmed in part by using carbon fibre spokes, and improvements made in aero efficiency and structural stiffness. They have decreased in weight by up to 220 grams per wheelset. The savings come from a new structure and better rim layups, with new carbon spokes.
- The C36 has dropped 180 grams, and now weighs 1170 grams.
- The C50 has dropped 159 grams and now weighs 1302 grams.
- The C60 has dropped 220 grams and now weighs 1389 grams.
The wheels are optimised for 28-30mm tyres, and the cup and cone bearing system Shimano has long favoured has also remained. Shimano has also built in the ability to adjust bearing preload whilst the wheels are installed in a bike.
The wheels have 23mm internal widths and front- and rear-specific rim profiles. External widths have been engineered to balance ‘aero and crosswind stability’.
There aren’t any major aero claims or data to look at, but Shimano has cited up to a 2.7-watt aero drag saving at 48 km/h with 30mm tyres, we assume across the board as no specific combination is listed.
The brand also cites CFD simulations and performance across ‘real world’ yaw conditions, not just ‘idealised wind tunnel angles’.
Since we started spotting prototype Shimano wheels, their carbon fibre spokes have been a talking point, and the new wheels will all feature new Shimano carbon spokes.
There will be two carbon fibre spoke variants depending on the wheelset: the ‘Super Aero’ spokes have a 5.2mm x 0.8mm profile, whilst the regular ‘Aero’ spokes have a 4mm x 1.1mm profile.
Shimano says the spoke type and count are tailored per model to create the intended ride characteristics depending on the application: fast aero wheel, climbing, etc.
The cup and cone bearings remain in place; Shimano says this "allows rotational torque to be optimised when installed on the bike."
Shimano has favoured cup and cone bearings historically on most of its wheels, and says they demonstrated "significantly lower friction than typical cartridge-bearing setups" in comparative testing.
Shimano cited a test involving wheels with cartridge and cup-and-cone bearings. Both had 500n of vertical force applied, which represented the bike and rider. A further 200Nm of thrust force and 5000N clamp force were applied via the thru axle. The test showed a 30% lower rotational torque for the new cup and cone bearings.
Bearings are said to be now replaceable, but this has long been the case; bearing cups are now also replaceable and waterproof sealing has been improved.
Shimano Dura-Ace C36
- The updated C36 wheels will have part number WH-R9370-C36-TL.
- Claimed weight is 1170 grams per pair.
- 23mm internal rim width, 29.4mm external rim width.
- Aero spokes, 18 front, 21 rear.
- Price: Front: £1,099.99 Rear: £1,199.00 / US pricing TBC.
Shimano Dura-Ace C50
- The C50 wheels will have part number WH-R9370-C50-TL.
- Claimed weight is 1302 grams per pair.
- 23mm internal rim width, 31mmm external front rim width and 32mm external rear width.
- Aero spokes, 21 spokes front and rear.
- Price: Front: £1,099.99 Rear: £1,199.00 / US pricing TBC.
Shimano Dura-Ace C60
- The C60 wheels will have part number WH-R9370-C60-TL.
- Claimed weight is 1389 grams per pair.
- 23mm internal rim width, 31.5mm external front rim width and 32.3mm external rear width.
- Aero spokes, 21 spokes front and 24 rear.
- Price: Front: £1,099.99 Rear: £1,199.00 / US pricing TBC.
New Shimano Dura-Ace C99
- This is the new C99 aero front wheel for TT and Triathlon, and has the part number WH-R9370-C99-TL-F.
- 99mm rim depth.
- Claimed weight is 792 grams.
- 23mm internal rim width, 35.2 mm external rim width.
- 16 Super Aero spokes.
- Price: Front: £1,199.99 / US pricing TBC.
New Shimano Dura-Ace Disc
- This is the new R9370 D disc wheel for TT and Triathlon, with part number WH-R9370-D-TL-R.
- Designed to pair with the C99 front wheel.
- Claimed weight is 987 grams.
- Full disc construction.
- Price: £2,299.99 / US pricing TBC.
