Cyclist
New Roval Rapide III wheelsets save weight with a deeper front than rear wheel rim
Specialized’s Roval component brand has launched three different models of its Rapide wheelset: the Roval Rapide Sprint, CLX III and CL III. They all have a deeper front than rear wheel, as Roval says that this delivers 90% of the aero gains from matched depth front and rear wheels with significantly lower weight as well as greater comfort.
The Roval Rapide Sprint and Roval Rapide CLX III wheelsets are priced at £2,998 and the Roval Rapide CL III at £1,548.
Roval Rapide Sprint
The Roval Rapide Sprint, as its name says, is designed for sprinting. The wheelset has a claimed weight of 1,395g (640g F, 755g R) and, unusually, the front rim at 63mm, is deeper than the 58mm rear rim. Roval claims that this is because 90% of the aero benefits come from the front wheel.
All three new wheelsets have 21mm internal width and are aero optimised for 28mm wide tyres – Specialized tyres preferred – although Roval says that its wind tunnel testing shows aero benefits with tyres from 26mm to 30mm in width.
The hubs get Roval hub bodies with internals from DT Swiss’s top spec 180 hubs with SINC ceramic bearings. Roval says that they shed over 50g from its previous generation hubset.
There are new Aero Composite spokes with titanium nipples and hub fixings that the brand says weigh 1.9g each, so that the wheel’s spoking in its entirety is 96.6g lighter than steel, as well as being 20% stronger.
Roval reckons that its low weight/aero-at-front design might save 18cm in a 250m sprint. It’s a similarly marginal gain for the pros to the 32cm advantage in a sprint claimed when it launched its one-piece Roval Rapide Cockpit.
Roval Rapide CLX III
The top spec Rapide CLX III wheelset has also had an upgrade, which sees a deeper 51mm front rim paired with a 48mm depth at the rear. Roval claims a 1,305g wheelset weight (600g F, 705g R), making the new wheelset 215g lighter than its predecessor. While the Rapide Sprint wheelset is designed for sprint finishes, Roval says that the Rapide CLX III is faster on mixed road courses and its 1,265g Alpinist wheelset is best for climbing stages.
As with the Sprint wheelset, the use of carbon spokes accounts for around 100g of the weight loss, while there’s the same Roval hubset with DT Swiss 180 internals and ceramic bearings. Roval says that a further weight saving comes from a new carbon fibre layup in the rim.
Price for both the Roval Rapide Sprint and Rapide CLX III front wheels is £1,299 ($1,500, €1,499), for the rear it’s £1,699 ($2,000, €1,999), totalling £2,998 (£3,500, €3,498) for the pair.
Roval Rapide CL III
Finally, there’s the slightly less flashy Rapide CL III wheelset. This shares the same 51mm front, 48mm rear profiles as the CLX series wheels, but swaps to DT Swiss Competition Race steel spokes and DT Swiss 350 hubs with stainless steel bearings. The claimed wheelset weight is 1,555g (716g F, 839g R), 35g lighter than the previous generation CL II wheelset.
The CL III front wheel is priced at £719 ($950, €849) and the rear at £829 ($1,250, €949), totalling £1,548 ($2,200, €1,798).
Why the deeper front wheel?
Many aero bike wheelsets have the same rim profile and depth front and rear. In some cases, there are different wheel depths and profiles between the front and rear wheel though. Where this is the case, the rear wheel rim is typically deeper than the front rim and often narrower and more pointy.
The logic is that the front wheel is more prone to twitchy handling in crosswinds, while the deeper rear rim can act as a powerhouse, offering greater aero gains.
Roval reckoned that it cracked the crosswind gust problem with the first generation of its front wheel though and has carried the same profile through to the new third generation wheels. It says that its shape helps to maintain front wheel stability in gusts of 0.5 to 2 seconds, which it believes is the gust frequency that riders find hardest to handle.
Roval has turned the conventional thinking on wheel depth on its head, as it points out that airflow at the leading edge of the bike matters more than the rear. So when it tested mixing a 64mm deep front wheel with a 35mm deep rear, it reckoned that the aero gains were 90% of those from a matched 64mm deep wheel pair. The mismatched wheels saved a chunk of weight though, for faster acceleration and climbing. Roval also says that the shallower rear wheel is more comfortable.
It’s the same logic as applied to many of the current crop of the best aero bikes, where deep sections to the head tube, fork legs and down tube are paired to a slimmed down seat tube, seatpost and seat stays, allowing whole bike weights to head down towards the magic 6.8kg UCI weight limit.
All three of Roval’s new wheelsets share their optimization for 28mm tyres and run on Roval LF hubs with DT Swiss internals. All three have rims with hooked beads, which are wider than in the previous generation wheels. There’s a 39% claimed increase in pinch flat protection and improved tubeless tyre retention in an impact thanks to the rim’s 4mm wide bead hooks. They’re wider than in the previous generation wheels and wider than many competitors, although that begs the question whether the more stepped tyre-to-rim interface increases drag.
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