Roval launches revamped Rapide CLX II and Alpinist CLX II wheelsets – and this time they are tubeless

Roval has launched updated versions of its premier aero and climbing wheelsets – and this time they are tubeless.

The Roval Rapide CLX II and Alpinist CLX II wheelsets aren’t revolutionary, but they’re finally up to speed with tubeless compatibility and, according to the US brand, offer refinements aimed at keeping them at the front of the pack.

Updates include a revised carbon design that allows for tubeless compatibility – Roval’s testing of the original Alpinist wheelset resulted in a tubeless tyre blow-off after Peter Sagan cracked a rim – and improved tyre setup. Roval continues to use a hooked rim design.

The Roval Rapide CLX II is an aero wheelset with variable rim depths (51mm at the front, 60mm at the rear), weighing 1,520g (including tape and tubeless valves).

The Rovale Alpinist CLX II, meanwhile, is a lightweight, climbing-focused wheelset with a 33mm-deep rim and 1,265g weight (again, including tape and tubeless valves).

Both the Rapide and Alpinist have an internal rim width of 21mm and are optimised, according to Roval, for use with 26mm tyres. The Rapide wheelset is priced at $2,800 / £2,500 / €2,500 and the Alpinist at $2,650 / £2,500 / €2,500.

False start

When the original Rapide CLX and Alpinist CLX wheels launched in June 2020, Roval explicitly said they were for use with inner tubes, despite the growing momentum behind tubeless tyre technology on the road. (Specialized had also pushed for tubeless adoption in the previous year, with Fabio Jakobsen among the riders to win on the brand's new Turbo RapidAir tubeless tyre – ed.).

This time around, the second-generation wheels are tubeless-ready – so why weren’t they to begin with?

Tubeless tyres are well established in mountain biking and have been for more than a decade. On the road, however, the lower volume tyres and higher pressures introduce new factors and, according to Roval, new opportunities for failure.

This became apparent in 2019 while Peter Sagan was testing the then-still-to-be-released Alpinist CLX at a Bora-Hansgrohe training camp. Roval says the three-time world champion jumped a roundabout, came up short and impacted the curb. The result was a broken carbon rim with a tubeless tyre that blew off during the impact.

Yes, Sagan was using tubeless tyres, and Roval says the original Alpinist and Rapide wheelsets were initially designed for tubeless use.

Roval says the issue wasn’t that Sagan’s rim cracked – both of the original wheelsets had passed the UCI’s 40 Joule drop test (an impact test on a bare carbon rim) – but that the tubeless tyre didn’t remain seated, posing a crash hazard to the rider.

“Road tubeless presents different rim failures,” said Jeff Meyer, engineering manager at Roval. “The higher pressures of road wheels leave very little margin for error. A small crack quickly becomes a larger one.”

Testing demonstrated that tubes dissipated the impact, while a tubeless tyre acts like a tightly wound spring, quickly releasing energy, resulting in blow-offs.

As a result, Roval decided to play it safe. The quick fix for Roval’s WorldTour teams – and for specification on Specialized bicycles – was to release these wheels as tubed clinchers.

“[The teams] wanted the aero benefits and were willing to sacrifice tubeless. We ran the data, and they were faster than the previous generation with Turbo Cotton tyres, which approach the performance of tubeless,” said Ben Edwards, Specialized’s director of global marketing.

So what’s different this time round? The new design sports a revised carbon layup that, according to Roval, transfers the impact force away from the tyre bead. If the rim cracks under a severe impact, it will do so in the spoke bed.

This failure mode ensures the tubeless tyre remains inflated and the “pressure vessel”, as Meyer calls it, remains intact, allowing the rider to come to a stop safely. Roval says it’s currently using this data to lobby for a more rigorous industry-wide road tubeless test standard.

Still hooked

It's worth noting that both of Roval’s new wheelsets feature hooked beads.

While some of the brand’s competitors, including ENVE and Zipp, have moved to hookless rims, Roval has stayed the course.

According to Roval’s product manager Chris Wehan, the reason is to provide riders an additional layer of security and to offer the broadest range of compatibility with the best road bike tyres, both tubed and tubeless.

“We have a really great process of building hooks into our rims that doesn’t sacrifice strength or cut fibres,” Wehan said.

Roval has, however, made some subtle changes to the interior profile of the rims to ease the installation and removal of stubborn tubeless tyres. To achieve this, the Roval team reduced the circumference of the bead seat by 1.4mm.

According to Wehan, this is still well within the ETRTO tubeless range, but not on the highest end of the spectrum, which was the case with previous Roval wheelsets. This slight adjustment makes it easier to seat tubeless tyres with a regular floor pump and to swap tyres with minimal frustration.

Aero meets stability

As with the previous version of the Rapide, the main story behind this wheelset is “aero meets stability”. The rim profiles are the same as its predecessor, with a bulbous, 35mm-wide (external) front rim designed to damp steering input and keep the rider from overcorrecting in crosswinds.

According to Roval, the Rapide CLX II comes within 0.5 seconds of the deeper CLX 64 in a 40km time trial and is two seconds slower than a 100mm-deep time trial wheel over the same 40km course, with better overall performance as yaw angles increase.

The Rapide CLX II may cut the same silhouette through the wind as the original, but it does have some changes to the carbon layup that result in a 100g weight gain over the previous version, weighing in at 1,520g with tubeless valves and tape. According to Meyer, this weight gain plays a role in redistributing impact forces away from the exterior of the rim.

Roval took this opportunity to shave material from the hub shells for aero gains, incorporating the DT Swiss EXP freehub system and adding Sinc ceramic bearings – an upgrade that most of Roval’s sponsored teams were already reportedly making.

Breaking out of the pigeonhole

Roval's changes to the Alpinist CLX II are less dramatic than with the Rapide CLX II.

The shallower, 33mm rims are also reinforced with additional layers of carbon, but the overall wheelset weight was kept the same thanks to an updated hubset with excess material removed from between the disc mounts. It follows suit with DT Swiss EXP hub internals and Sinc ceramic bearings.

According to Specialized’s Ben Edwards, the Alpinist CLX II is designed to be the lightest, best-handling wheelset on the market.

“We think this wheel got pigeon-holed a little bit,” he says. “It’s a climbing wheel, but it’s also a wheel for anyone who wants to improve the ride quality of their bike. This is the wheelset most riders should probably be on.”

Stay tuned

We’re currently testing both wheelsets and will report back with long-term reviews.