The new WH-R9370 series replaces the previous DURA-ACE R9270 generation. It therefore offers a glimpse of a new Dura-Ace groupset, which – under the 9300 designation – is presumably already in the pipeline. The current 12-speed groupset was unveiled in 2021. The new wheelsets, featuring camouflaged branding, have already been spotted in professional races this season, including on the bike of Tour de France stage winner Matthieu van der Poel. During development, Shimano collaborated with professional triathletes and the Alpecin – Premier Tech Cycling Team and Fenix – Premier Tech Cycling Team. Triathlete Kat Matthews and Mathieu van der Poel provided feedback on acceleration performance, sprint stability and crosswind behaviour.
With its new wheelsets, Shimano is focusing on road racing, time trials and triathlons. The C36, C50 and C60 models cater to different areas of use. The C99 front wheel and the disc wheel are primarily aimed at time trialists and triathletes.
Range of models for various applications
The C36 is suitable for mountainous terrain. Its low weight of 1,172 grams per wheelset aids acceleration on climbs. The C50, weighing 1,302 grams, is suitable for a variety of race profiles. The C60 weighs 1,389 grams and has been designed for fast flat stages and sprints.
The C99 front wheel minimises aerodynamic drag at very high speeds. Combined with the disc wheel, it creates a system designed for time trials and triathlons.
Weight reduction through a new design
The C36 wheelset weighs 1,172 grams. That is 178 grams less than the previous model. The C50 reduces the weight from 1,461 to 1,302 grams, a saving of 159 grams. The difference is greatest for the C60, at 218 grams: from 1,609 to 1,391 grams.
Shimano has achieved this weight reduction through new carbon spokes and revised carbon lay-ups in the rims. The rim, hub and spokes were developed as an integrated system. The C36 mountain bike wheelset uses 18 aero spokes on the front wheel and 21 spokes on the rear wheel. The all-rounder C50 uses 21 spokes on both the front and rear wheels. The C60 features 21 spokes at the front and 24 at the rear.
Carbon spokes in two versions
The carbon spokes are available in two versions: the Super Aero variant has a cross-section of 5.2 mm × 0.8 mm and is used exclusively on the C99 front wheel. The Aero spokes, which are used on the C36, C50 and C60, measure 4.0 mm × 1.1 mm.
Rim width for modern tyre sizes
All models in the WH-R9370 series have an internal rim width of 23 mm. This dimension is suitable for tyres between 28 and 30 mm wide. The external widths vary depending on the design: The C36 has an outer width of 29.4 mm on both the front and rear wheels. On the C50, the front wheel measures 31.0 mm and the rear wheel 32.0 mm. The C60 measures 31.5 mm at the front and 32.3 mm at the rear.
Shimano developed the rim profiles using flow simulations and validated them in aerodynamic tests. The tests were carried out at 48 km/h with 30 mm tyres. The new generation is designed to reduce aerodynamic drag by up to 2.7 watts compared with the previous model. The development process took into account realistic approach angles during riding.
New tapered roller bearings with replaceable components
The WH-R9370 wheelsets continue to use Shimano’s cup-and-cone bearing system. This system allows the bearing play to be adjusted after fitting to the bike. A new feature is the replaceable bearing cups, which simplify maintenance. The seal against water and dirt has also been improved.
Shimano tested the cup-and-cone system against conventional industrial bearings. The test conditions included a vertical load of 500 newtons, a forward thrust of 200 newtons and a clamping force of 5,000 newtons from the thru-axle. According to the manufacturer, the cup-and-cone system reduces rotational torque by 30 per cent compared with industrial bearings.
The first models in the WH-R9370 series will go on sale from September 2026.
Technical specifications:
WH-R9370-C36-TL:
- Weight of wheel set: 1172 g
- Internal jaw width: 23 mm
- External width: 29.4 mm (front and rear)
- Front spokes: 18 aero spokes
- Rear spokes: 21 aero spokes
WH-R9370-C50-TL:
- Weight of wheel set: 1302 g
- Internal jaw width: 23 mm
- Front external width: 31.0 mm
- External width at the rear: 32.0 mm
- Front spokes: 21 aero spokes
- Rear spokes: 21 aero spokes
WH-R9370-C60-TL:
- Weight of wheel set: 1391 g
- Internal jaw width: 23 mm
- Front outer width: 31.5 mm
- External width at the rear: 32.3 mm
- Front spokes: 21 aero spokes
- Rear spokes: 24 aero spokes
WH-R9370-C99-TL-F:
- Weight: 792 g
- Rim height: 99 mm
- External width: 35.2 mm
- Spokes: 16 Super Aero carbon spokes (5.2 mm × 0.8 mm)
- Front wheel only
WH-R9370-D-TL-R:
- Weight: 987 g
- Design: Solid-disc rear wheel
All models:
- Bearing system: cup-and-cone with replaceable bearing shells
- Tyre width: 28–30 mm
- Availability: from September 2026
Jens Klötzer
Editor