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Cadex claims best-in-class performance for new 50 Ultra Disc wheel system with aero tyres

Cadex has a battery of tests against its competitors to back up its impressive aero claims

Paul Norman
15 Aug 2022

Cadex says that its 50 Ultra Disc wheel system is ‘designed for maximum aerodynamic efficiency, while also providing stability and control in all conditions’.

Rather than describing its new wheels as a wheelset, it calls them a ‘wheel system’, as they’re optimised to work with the brand’s new 25mm Cadex Aero tubeless tyres.

Cadex claims its wind-tunnel testing shows the 50 Ultra Disc wheels to be the fastest in their category and they come with a range of top end tech, including aero carbon spokes and ceramic bearings. That leads to a claimed overall weight of 1,349g.

The Cadex 50 Ultra Disc wheels have seen pro-level action with Team BikeExchange-Jayco this summer; Simon Yates won Stage 14 of the 2022 Giro d’Italia on the new wheel/tyre system and Michael Matthews was also using the wheels on some stages of the Tour de France.

We also spotted the new wheels in Luke Durbridge’s bike at the Tour de France, which we believe is the as-yet-unreleased new Giant Propel.

The rims of the new wheels, as you’d expect, are 50mm deep. They’re also 22.4mm wide internally and 30mm externally, with a hookless bead.

Cadex says that it’s chosen this width and the hookless design to ensure a smooth transition between the Cadex Aero tyre and rim, and that going hookless increases the bead-to-bead width by 3.8mm over a hooked design.

Zipp has made all its road wheelsets hookless and Enve recently overhauled its SES line of wheels, adopting the feature too. These changes were made in part to optimise their wheels’ aerodynamics in a similar way to Cadex.

Aero tested against the competition

Cadex says it has wind-tunnel-tested the 50 Ultra Disc wheels against Enve SES 5.5, Zipp 454 NSW, DT Swiss 50 ARC 1100 and Roval Rapide CLX wheels, running them through four different tests. That included wheel-only tests both with its new Aero tyres and with competitor tyres.

Cadex also tested the wheels and tyres mounted into complete bikes with a helmeted mannequin aboard, using a Giant Propel Advanced SL Disc, Specialized Tarmac SL7, Canyon Aeroad CFR Disc and Cervélo S5.

Its test wind speed was 40kmh and it tested at yaw angles up to 20 degrees to measure drag and side load on the wheels.

According to Cadex’s tests, its own wheel/tyre combo came out tops in all the tests (well, they would say that wouldn’t they?). The Cadex wheels are also lighter than all the competition and Cadex claims that their lateral stiffness to weight ratio is up to 41 per cent higher than their competitors.

Comparative tests and watts-saved figures need to be taken with a pinch of salt, as every brand seemingly claims its wheels are faster and more aero and every brand tests under slightly different conditions.

But nevertheless, we were impressed with how well the Cadex 36 Disc and Cadex 42 Disc wheelsets rode when we tested them, and judged them on a par with brands like Enve and Zipp, so we’d expect a similar level of performance from the new Ultra 50 Disc wheel system.

New components

Cadex uses its own ‘directional’ aero carbon spokes in the new wheels. The Dynamic Balanced Lacing system claims to offer a wider bracing angle and uses slightly different length forward-facing and rearward-facing spokes to even out spoke tension when pedalling.

There’s also a new third-generation aero hub design and a new freehub with 40 points of engagement. Cadex has used its own ceramic bearings in the hubs to reduce rolling resistance by, it says, up to 30 per cent over steel bearings.

As you might expect, with all Cadex’s tech and testing thrown at them, the 50 Ultra Disc wheels don’t come cheap.

The wheels are priced at £1,149.99 (€1,300, $1,500) for the front and £1,699.99 (€1,650, $2,000) for the rear – a complete wheelset price of £2,849.98 (€2,950, $3,500). They’re available with a Shimano HD, SRAM XDR or Campagnolo freehub and likely to be on sale around October.

Matching Cadex tubeless tyres

Surprisingly, given that Cadex says that the 50 Ultra wheels are optimised for wider tyres, the new Aero tubeless tyres are only available in 25mm width. That’s quite narrow in today’s world where even an aero bike like the new Cervélo S5 has clearance for 34mm rubber.

Cadex doesn’t quote real world width, although sitting on the wide 22.4mm internal width rim of the Cadex 50 Ultra wheels, the measured size of the tyre is likely to be closer to 28mm.

But width isn’t the name of the game with the new tyre. Its layup and casing are designed to take on a taller, narrower profile with flatter sidewalls, for a smoother, less lightbulb-esque interface between the tyre and the rim’s hookless bead, cutting down on drag.

There’s a new tyre compound in Cadex’s tyre too, called RR-A that it says lowers rolling resistance by 15 per cent relative to its older RR-S compound. There’s a file tread and a swoosh pattern at the shoulder with a smooth centre tread and a 170TPI casing with Kevlar puncture protection belt.

Cadex says that the Aero tyres will give an aero benefit with other brands’ hookless rims, not just as part of the 50 Ultra wheel system.

As with the wheels, Cadex has a battery of comparative tests to back up its claims. Testing at 40kmh, the brand says that the tyre, when mounted on its new wheels is 2.3 watts faster than a set of 25mm Conti GP 5000 tyres on DT Swiss 50 ARC 1100 wheels and 5.5 watts faster than 25mm Vittoria Corsa TLR tyres on Enve SES 5.6 wheels.

Pop its tyres on the Enves and Cadex claims that drag drops from 10.5 watts to 5.3 watts. Note that these figures pertain to aero only, not rolling resistance, for which you'd need to account to get the full picture.

The Cadex Aero tubeless tyre is priced at £64.99 (€72.50, $100). 

More info on the new wheels and tyres on

Cadex 50 Ultra Disc tubeless wheelset

  • Material: Carbon
  • Rim type: Hookless
  • Rim height: 50mm
  • Internal rim width: 22.4mm
  • External rim width: 30mm
  • Axle compatibility: Front 100×12 thru-axle, Rear 142×12 thru-axle
  • Hub compatibility: Shimano HG, SRAM XDR, Campagnolo
  • Bearings: Cadex ceramic
  • Spokes: Aero carbon spokes w/ alloy nipples, 21 front / 24 rear
  • Driver: 40 tooth ratchet
  • Extras: Rim tape and valve included
  • Weight: 1,349g (pair), 595g (front) 754g (rear)
  • Price: £1,149.99 (front) / £1,699.99 (rear)

Cadex Aero tubeless tyre

  • Size: 700×25mm
  • Weight: 290g
  • Min Pressure: 70 PSI / 4.8 Bar
  • Max pressure: 115 PSI / 7.9 Bar
  • Casing: 170 TPI
  • Bead material: Kevlar/Carbon Composite
  • Bead type: Folding
  • Compound: RR-A
  • Puncture Protection: Race Shield
  • Price: £64.99

Like fancy wheels? Read our coverage of Zipp's 858 NSW and 808 Firecrest launch

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