Mavic has launched its latest carbon road wheelset, the Cosmic Ultimate 45 Disc, weighing just 1,255g (claimed) thanks to the use of novel carbon spokes.

Priced at ?3,575, Mavic says the top-of-the-range wheels balance low inertia and high lateral stiffness, with the low weight, durability and aerodynamics of the handmade carbon rims and spokes.

The new Cosmic Ultimate 45s are 45mm deep, disc brake-only clinchers and, thanks to a neat rim construction, are tubeless compatible.

As the rim bed is undrilled, rim tape isn’t required, which Mavic says provides a user-friendly tubeless system and further saves on weight.

It’s the French company’s first major road wheel release since it was placed into receivership in 2020 because of financial difficulties.

It was bought a few months later by French investment firm the Bourrelier Group, who provided the cash to develop this new wheelset.

Mavic Cosmic Ultimate 45 Disc: Handmade in France

The Cosmic Ultimate 45 Disc is handmade in Mavic’s new headquarters in Annecy and is the only wheelset made entirely on-site.

‘We use five different types of carbon fibre, and each wheel is made from 71 pieces,’ says Mavic research and development product manager Sebastian Lejeune, who developed the new wheelset.

‘We have a team of ten people who build and assemble the wheels. It is a very particular job as we have designed the whole process and machines ourselves, so each person has gone through 3-4 months of training.

‘Each wheel takes eight hours to assemble, and then when you add in the baking process it adds up to between 1.5-2 days for one wheel.’

The Cosmic Ultimate 45 also comes with a label showing the names of the people who made and assembled the wheels at the key production times, as well as an offcut of the carbon fibre used during creation.

Balancing act

Mavic says the Cosmic Ultimate 45 wheelset balances lateral stiffness, weight and ease of use.

‘The new Ultimate doesn’t favour extreme light weight above all else,’ explains Maxime Brunard, head of product management at Mavic. ‘Instead, we chose to balance inertia against lateral stiffness to ensure the wheels provide excellent all-round performance.’

This notion of balance can be seen in the wheel’s dimensions, which could be considered conservative when measured against modern trends, but Mavic is confident its rationale stacks up.

‘The Ultimate uses hooked rim walls, 45mm deep rims with 19mm internal width and 28mm external width. It can be used with 25mm, 28mm and even 32mm tyres,’ says Brunard.

‘We don’t believe that all customers are ready to be limited by 75psi or only use 28mm tyres, so we haven’t gone hookless or super-wide with the wheels’ internal width. The wheels are still wide on the outside if the user wants to use wide tyres.’

Durability

While the wheels as a whole are lightweight, the hub weighs more than the previous Cosmic Ultimate.

‘Compared to the previous model [which was tubular] we are using bigger bearings that are a little bit heavier, but the weight of the hub doesn’t matter as much as the weight on the outside,’ says Brunard.

‘We needed to gain some stiffness and durability from the hub, hence the bigger bearings, but they are much more durable and also provide a lot of stiffness together with the axle.’

The hub has aluminium axles, ratchet and standard bearings and the shell is wrapped in carbon.

Carbon spokes

The Cosmic Ultimate 45 wheels are laced with carbon spokes that Mavic describes as ‘rim to rim’ (R2R), meaning each spoke starts on one side of the rim, then wraps around the hub shell before inserting into the other side of the rim.

Mavic claims that the R2R technique means that there is constant, homogeneous 150daN tension, which ensures ‘perfect’ wheel alignment.

‘CNC and heat-treated aluminium inserts connect the spoke to the rim,’ explains Lejeune.

‘The spoke is bonded and then screwed onto the rim. This also makes it easier for repairs if something breaks as we can cut all the spokes, remove them and reuse the rim. There is also a tiny fibre in each spoke that stops it from shattering should it break.’

According to Mavic, the bonded spokes can resist up to 6000N traction, meaning that two spokes are supposedly strong enough to suspend the average car. Mavic hasn’t actually tested that, though.

Built to last a lifetime

The Cosmic Ultimate 45 Disc has undergone significant testing in Mavic’s HQ, where it has a purpose-built testing area.

409 impact tests and 407 traction tests were carried out on the spoke attachment and, according to those tests, the new carbon spokes are four times stronger than the previous R2R design.

The wheels have also been subjected to 35 lab tests, including climate chamber ageing and a host of impact and endurance tests to ensure it will perform on different roads and in different conditions.

Mavic also offers a lifetime warranty on all its carbon wheels.

Mavic Cosmic Ultimate 45 Disc specs

Weight: 1,255g (pair) 575g (front) 680g (rear)
Material: carbon fibre
Height: 45mm
Internal width: 19mm
External width: 28mm
Disc brake specific
No tape tubeless profile
Spokes: 10 R2R unidirectional carbon fibre on each wheel
Hubs: 12×100 thru-axle (front) and 12×142 thru-axle (rear) (opt QR adapters)

Photos: Mavic