New Cadex Ultra 50 Disc wheels are fast and efficient: first ride review

Light, hookless and paired with an all-new propriety aero tubeless tire, the Ultra 50s take us deeper into the disc brake era

Cadex Ultra 50
(Image credit: Cadex)

Already spotted on the WorldTour being raced by the Bike Exchange - Jayco team, Cadex today officially launched its all-new Ultra 50 wheelsystem, complete with a optimized tubeless tire. 

Cadex, which is nested under bike manufacturer Giant Bicycles, already had 36mm, 42mm and 65mm deep wheels available, but with the Ultra 50s Cadex presents its lightest, fastest and most high-tech offering yet.

Away from the World Tour, Cadex has also been making headlines in the triathlon world as of late. Cadex is the bike sponsor Olympic gold medallist and Ironman World Champion Kristian Blummenfelt, whose unconventional (no top tube, anyone?) custom Cadex Tri bike raised many eyebrows at the Ironman World Championship. 

Cadex has long been experimenting with composite products, frames and wheelsets alike.  The brand got its start in the 1980's when Giant wanted to be among the first brands to mass-produce carbon bike frames, which at the time were far outnumbered by aluminum alloy frames. 

Cadex succeeded in releasing a carbon road bike and mountain bike frame, but as carbon frames became increasingly popular, the idea of a carbon bike was absorbed into the larger Giant-brand offerings and the idea of Cadex went into hibernation — until 2019.

In 2019, Cadex officially relaunched with the goal of making the best, most aerodynamic products in the bike industry. 

With the launch of the Ultra 50 wheels, Cadex says it took a “spare no expense” approach to demonstrate just how much riders stand to gain when leveraging Cadex-engineered products. 

Cadex Ultra 50

(Image credit: Cadex)

The Tech

The Cadex Ultra 50 wheels were built with one thing in mind: saving watts. From the flat spokes to the proprietary hub and Aero Tubeless tires, the entire wheelsystem is designed to move riders forward, faster and on fewer watts. 

Disc-Only

Rim brake bikes, and the matching wheels, are becoming a thing of the past. As such Cadex is the latest brand to go disc-brake only in their offerings. The Ultra 50 wheels are only center lock disc brake compatible, and the wheels do not come with their own rotors and lock ring. You’ll need to provide these on your own. 

Hookless & Made for the Aero Tubeless Tire

The Ultra 50 wheels are a hookless tubeless design, and come ready for tire installation with rim tape already set. While other industry favorites such as Continental 5000s or even Cadex’s own Cadex Race tires cab certainly be used, the wheels were optimized around the brand's own new tire, the 25mm Aero Tubeless. 

The Aero Tubeless takes on an ovular shape when installed and inflated. This helps the tire maintain an entirely svelte aerodynamic profile, with no tire 'spillage' over the edges of the rim. Traditionally, tires take on a circular shape when inflated and a tiny bit of the tire’s profile extends past the rim, which Cadex claims, causes drag. 

Although not quite as grippy as other tires I've ridden, I found the aero tubeless handle well and are reinforced with multiple layers to - along with sealant - provide the best possible protection against punctures and flats. 

Flat Spokes

In what is the most visually obvious feature of the Ultra 50s, the flat spoke design serves more than just an aerodynamic purpose. 

Cadex wanted to ensure that these wheels’ spokes could withstand the same level of impact as a stainless steel spoke; they say these actually exceed it and provide a more stable ride than wheels with traditional spokes.

This is achieved by a fully-integrated spoke. Most spokes have a nipple where they meet the rim. The Ultra 50s’ spokes, upon completion of their carbon and aluminum layering process, are chemically bonded to the rim, not mechanically joined via a nipple as with other wheels. The spokes on the Ultra 50s will essentially never fail or become dislodged.

Proprietary Hub

The piece de resistance for these wheels is the proprietary hub. 

Cadex completely redesigned the idea of a hub for the Ultra 50s, moving many of the sealing elements of the hub to the freehub body, reducing the friction of the overall hub system. 

Cadex also opted to use chromoly-43, a compound used in locomotives and automobiles. While it may be slightly heavier than other hubs, the material is extremely stable and durable and allows for the wheel to take significantly higher torque loads than its competitors. 

The real differentiator is in the Cadex’s proprietary “Dynamic Balanced Lacing” where the spokes meet the hub. 

In other wheels, for every pedal stroke, there is a pushing spoke and a pulling spoke. Although it takes just a nanosecond to complete, there is a “wind up” time between you pushing down through the pedal stroke and that power being transferred through the spokes and hub to ultimately propel the wheel and bike forward. In that “wind up” time, some power is lost as the “pushing” spoke flexes slightly under the torque.

In the Ultra 50s, the leverage angle has been moved from the center of the hub to the outside of the rim, reducing energy expended on the “pushing” spoke and increasing it on the “pulling” spoke, meaning that significantly less power is lost per pedal stroke. 

Cadex Ultra 50s with Aero Tubeless Tires

(Image credit: Cadex)

Price and Availability

US:

CADEX 50 Ultra front $1500

CADEX 50 Ultra rear $2000

CADEX 50 Ultra pair $3500

CADEX Aero tire $100

UK:

CADEX 50 Ultra front £1149.99

CADEX 50 Ultra rear £ 1499.99

CADEX 50 Ultra pair £2649.98

CADEX Aero tyre £64.99

CADEX Aero Pair £129.98

The wheels will be available in September at select retailers and directly from Cadex online.  

Cadex Ultra 50

(Image credit: Kristin Jenny)

First Ride Review

Unboxing these wheels is a luxury experience, just like riding them. They arrive in sleek black boxes with #Overachieve emblazoned on the side. The actual wheels are nested inside of protective cloth cases within the box. You feel like you’re part of an elite club opening them up.

Mounting the Aero Tubeless was a bit of a saga, but each person’s tubeless experience can vary greatly. The front wheel seated on the first try with a floor pump. The back wheel was determined to take some years off my life and required trying a floor pump, high volume pump, air compressor and CO2 cartridges before finally seating (— never underestimate the power of one of those little cartridges). Finally hearing that magical “pop” gave a tremendous amount of relief. 

It’s easy enough to install center lock rotors so long as you have some grease and a locking nut. All in all, if you’re confident enough to set up your own wheels, these are relatively easy to configure.

Although I’m a triathlete and TT bike gal at heart, I’m do also own a road bike, which just so happens to be a Giant equipped with disc brakes and good ol' fashion mechanical shifting. I headed out to some notoriously wind-blown roads east of Boulder to see just how stiff and stable these wheels actually are. 

The first thing I noticed was the benefit of the Dynamic Balanced Lacing. You truly feel as though every single watt pushed through the stroke is going toward moving the bike forward. The power transfer was smooth and fast. 

The wind wasn’t exactly ripping the day I tested these, but a few hearty gusts here and there proved to me that yes, these wheels are able to hold their own so long as a confident rider sits atop them. Like any wheels with some sort of deeper rim, there’s a control factor of the front wheel when wind rushes by. I was impressed by the way these wheels held their own. 

Cruising toward a false flat that’s perfect for some out-of-the-saddle sprint efforts, I stood up and smashed out some 15-second sprints. The wheels held their line without straining and flexing to do so. I have a pair of highly-flexible rim brake 65s on my TT bike and they tend to waver and even wobble under the stress of intense efforts. Not the Ultra 50s, they are stalwart and stable.

The final test was to rip down a descent. Although the rear hub makes so much noise it would be hard to hear someone riding right next to you, the sleek aerodynamics of the Aero Tubeless tires, the flat spokes, the wheels’ thin profile… it all comes together in a way that allows you to confidently corner at high speeds and tuck in for a straightaway.

My biggest question for the Ultra 50s and the Aero Tubeless is how they plan to move into the 28c space. It’s no secret that right now - bigger seems to be better when it comes to tires. The Ultra 50s are currently optimized for 25c Aero Tubeless tires, but I imagine that will need to change in order to remain appealing to road cyclists especially.

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