New ultra-lightweight wheels from Hunt: 32 Aerodynamicist UD Carbon Spoke

Hunt has just released its latest – and lightest –  climbing wheelset, with a claimed weight painstakingly just 14 grams off dipping below the sub 1.2kg mark. Perhaps even more impressively, the price stands at just £1,199 / $1,549 / €1,619, which includes Hunt’s H_Care lifetime crash replacement

Let’s put that into some perspective. 

German lightweight specialists, Lightweight, have their Meilenstein Obermayer wheelset which is claimed to weigh an incredible 935 grams – but those hoops are tubular and designed for rim brakes. The Obermayer Evo Disc matches the disc specific and tubeless-ready build of the Hunt 32 Aerodynamicist, but has a claimed weight of 1,230 grams and costs £7,058.00 / $8,695.00 – although with a depth of 48mm, it likely is more aero.

Australian wheel brand Partington has managed to create a set of tubeless-ready disc brake wheels that are claimed to be a little lighter, in some places being reported as 1,150 grams and in others a more modest 1,200 grams. But these wheels cost around four times as much as the 32 Aerodynamicists.

Brands such as DT Swiss, Mavic, Roval and Cadex simply don’t offer a wheelset in their line-ups lighter than these new ones from Hunt – price doesn’t even come into it.

It really is quite the feat. As you'd expect, a lot of tech that’s gone into these wheels so let’s start at the rims and work our way inwards...

The rims

Having started development into hookless rims back in 2016, the weight savings of the design came to about 10 – 15 grams per rim. Since then, continuing advances have allowed Hunt to winnow down the weight of the 32 Aerodynamicist rims to a mere 374 and 377 grams.

It also sees a simpler construction method, helping to reduce the cost of the wheels. At £1,199 / $1,519 / €1,379, they are notably less expensive than other performance wheelsets. Simpler construction also reduces the material wasted in producing the wheels – which is better for the environment too.

In line with the new ETRTO tubeless road guidelines for 25/28mm+ road tyres – with which the 32 Aerodynamicist UD Carbon Spoke is fully compliant – the maximum permitted tyre pressure is 72psi (5bar). So, if you’re running 25mm tyres and need higher pressures than that, you’ll have to switch to 28mm in order to stay within the correct bounds.

Although this is a climbing wheelset with the a focus on cutting the weight, this hasn’t been done entirely at the expense of its aero attributes. Still 32mm deep, the rims are fully in the realm of shallow section wheels – providing proportionally greatest the aero gains over a box section.

In combination with their depth, the rims share a similar truncated airfoil shape and rounded U-shaped profile to the other rims in the Aerodynamicist range, helping to keep the airflow stay attached for longer as it passes over the rim. The hookless profile and smoother transition from rim to tyre also helps reduce the wake behind the rim, resulting in lower drag

Finally regarding the aerodynamics, with an internal rim width of 21mm and an external rim width of 25mm, the profile has been designed to work best in combination with a 28mm tyre. 

Although this is still relatively wide, interestingly it is still narrower than the 23mm internal and 27.5mm external widths of some of Zipp’s latest wheels – which have even been optimised around narrower, 25mm tyres. Food for thought.

The spokes

Three years ago, Hunt launched its first UD Carbon Spoke wheelsets, providing the benefits of an increased stiffness-to-weight ratio over steel, whilst still remaining fully serviceable and enabling the wheel to be trued like any other.

At a claimed 2.7 grams per spoke (in an unspecified length), the spokes come in significantly lighter than those stalwarts of quality wheelsets, the Sapim CX-Rays. In a 260mm length, those come in at 4.3 grams per spoke, making them a whole 59% heavier – more than half as much again.

Naturally, carbon spokes increase the price over steel spokes, but as the design brief was for the ultimate in lightweight, for this launch the wheels are only coming with the carbon spokes. That said, Hunt isn’t ruling out a more price-point oriented steel spoke option down the line.

The hubs

The new Sprint SLC hubs are CNC machine’d from cold-forged 7075 aluminium alloy, offering an enhanced strength to weight ratio and befitting the feathery aspirations of the wheelset. The front hub weighs in 95 grams and the rear is 220 grams.

Despite those optimisations for minimal mass, they have still been designed to provide the reliability and serviceability that Hunts hubs have become known for. The strength and durability is said to be the same as Hunt’s original Sprint hubs. As such, there’s no reason why the other wheelsets shouldn’t benefit from the same advancements and the new hubs will indeed be rolled out to certain other models in the coming months. 

The hub engagement is pretty snappy at 7.5 degrees, although this metric is less of a concern for road bikes, as the larger gears mean there is minimal travel at the crank arms before the hub engages. It's much more noticeable mountain bikes and gravel bikes when in the lowest gears – still, it does bodes well for that use case.

The freehub employs a more traditional leaf and pawl system, rather than a ratchet design as other brands have been switching too. The reason for this is that, although a ratchet might have fewer moving parts than a lead and pawl, Hunt believes: “once you go down to the smaller angles of engagement … the issues around ratchet reliability … are prohibitive”.

More moving parts might give a greater range of ways for something to go wrong, but if each of those moving parts are highly reliable, you’ll run into fewer issues than with a simpler – but more temperamental – system. That said, with the technology continuing to evolve, Hunt is more than happy to make the switch if it looks like the performance will indeed be better.

Key specs and availability

The Hunt 32 Aerodynamicist UD Carbon Spoke wheels are available to order now from Hunt's website, and more information about the complete range of Aerodynamicist wheels can be found there too.

MSRP: £1,199 / $1,549 / €1,619

Dimensions: 25mm external, 21mm internal

Weight: 1,213g

Hubs: Sprint SLC 7.5 Hub, with an engagement rate of 7.5°. Multi-point pawls, with 48 ratchets within the hub shell. Centre-Lock Disc.

Bearings: EZO

Spokes: UD carbon fibre spokes with incredibly high strength, stiffness and weighing only 2.7g per spoke

Tyre compatibility: Hookless Tubeless tyres only, optimised for 28mm

Freehub options: Shimano/SRAM 8/9/10/11 speed, SRAM XD/XDR, Campagnolo 8/9/10/11/12 speed