Roval goes tubeless with new generation Rapide and Alpinist wheels

The story of why Roval waited this long to go tubeless

Roval Alpenist CLX II and Roval Rapide CLX II
(Image credit: Anne-Marije Rook // Future)

When Roval launched the Rapide CLX and Alpinist CLX wheelsets in 2020, it raised some eyebrows by not going tubeless. The brand’s message at the time was that the tube system was simply the fastest. But that wasn’t necessarily the complete story. 

Yes, these wheels were indeed the fastest, lightest and best all-around wheelsets Specialized’s sister brand had ever produced. And Roval is quick to point out that over the 2020 and 2021 seasons, Rapide and Alpinist wheels won more races on the World Tour than any other wheels — 155 race wins in fact. However, leading up to the 2022 season, Roval had every intention of adopting a tubeless system, until Peter Sagan destroyed one of the prototypes in training. 

In December 2019, Sagan and the Bora-Hansgrohe team were at winter camp, riding the Alpinist CLX wheels that were still in development. The story goes that Sagan was doing Sagan things: jumping a roundabout and running straight into a curb. The front wheel cracked and the tyre burst off. Sagan was unharmed, but the wheel was sent back to the lab for inspection. It had, after all, met all certifying bodies’ standards, including the UCI’s 40 Joule drop test, before it had been sent out for demo-ing. So why did it fail? How did it fail? And why did the tyre come off? 

Now, tubeless wheel systems have a different —and more dramatic— failure mode than tubed systems. In case of a big impact, such as Sagan’s antics, a tube can potentially act as a buffer, dispersing the pressure over a larger area and delaying pressure release. The wheel’s structure is therefore more likely to stay intact and the tyre will stay on, allowing the rider to safely come to a stop. Without a tube, cracks in a tubeless rim bed can spread into the rim cavity, and the resulting air pressure creates a failure of the entire system.   

While the development wheels would have met all relevant safety standards, the Roval engineers wanted to do better: to create a wheel that would remain structurally sound and keep the tyre on the rim, even if the rim cracked.

And so, the tubeless wheel design went back to the drawing board while the Roval-supported teams were informed that they'd be starting the 2020 season on the same  CLX wheels they raced in 2019. However, after getting a taste of these new wheels, the teams said no. Even paired with tubes, the wheels were faster, lighter and handled better than the existing models. Thus, the Alpinist and Rapide were launched as tube-type wheels, and the Roval engineers got started on what would become the brand’s biggest testing and development project yet. 

Yves Lampaert of Team Quick-Step - Alpha Vinyl at the 2022 Paris-Roubaix riding the new Roval Rapide CLX II

(Image credit: Getty Images)

Setting a higher standard

Now I won't go into the gauntlet of tests, physics, formulas and details that went into the 21 months of testing and development. But to summarise, engineers faced the daunting task of producing tubeless wheels that stayed true to their race-winning shape, weight and aerodynamic performance while also making them sturdy enough to stay structurally sound in case of a seriously big impact. They surveyed riders, completed dozens of new carbon layups and devised entirely new tests, testing standards and contraptions.

One test involved riders physically running their bikes into a sensor-filled, 6-centimetre high solid block of metal while going at least 32kph in order to measure accurate force information, which then was applied to a striker drop test.  Having handled the metal brick myself, I’ll admit I wouldn’t have had the guts to force my bike into such a path, but it’s reassuring to know these wheels could handle it. All in all, these tests resulted in a new internal impact standard that nearly doubles the current industry standards, 70 joules. To relate, hitting a pothole or railroad tracks at 32kph generates approximately 30 Joules of force. A 70 joule force impact would make staying upright very unlikely.  

In the end, the Rapide CLX II and Alpinist CLX II wheels unveiled to the public in May 2022, are the strongest Roval has ever made at the lightest possible weight.  Roval feels so strongly about their higher standards and testing procedures that they wrote a white paper and shared it with the relevant governing bodies. 

We already saw a glimpse of the new Rapides used at Paris-Roubaix and Remco Evenepoel won atop the Alpinists CLX II at Liège-Bastogne-Liège. So let’s have a look at the details.

Roval's impact testing

An all-new impact testing method: riders physically rode their bikes into a sensor-filled, solid block of metal while going at least 32kph in order to measure accurate force information, which then was applied to a striker drop test.

(Image credit: Roval)

Rapide CLX and Alpinist CLX: Generation II

Tubeless-Ready:

Late to the game, but Roval’s ‘winningest wheels’ are now available with the lower rolling resistance, better grip, and flat protection benefits of a tubeless system. 

Hooked Rims:

Roval opted for a hooked rim instead of a hookless system to ensure secure bead retention and tyre compatibility with most brands on the market. It also allows for inflation up to 110psi, if that’s your thing. With an internal width of 21mm, the rims can fit tyres between 24 and 38mm. Roval even promises an easier at-home set-up and roadside dismounting experience than ever before. The shifting of the outer rim diameter dimensions is said to create an extra 1.4mm of bead slack in the tyre for few tyre struggles. 

All-terrain:

Compatible with tyres up to 38mm, these wheels are ready to get rowdy, be it on the cobbles of the Paris-Roubaix or grinding gravel. 

Ease of mind:

Confident in their new impact standards, Roval backs the wheels with a lifetime warranty and a no-fault crash replacement policy.