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Mavic has a dual history of daring moves and odd conservatism, with absolute winners and horrible flops coming from both ends of that spectrum. The original Helium, for example, was so far out of the custom-built norm that it was an assumed failure before it ever hit stores. Of course, it changed the way we buy wheels forever. On the other side it has Zap and Mektronic, which barely got out of the starting gate.
The brand has been decidedly conservative, though, with carbon clinchers. It has stuck to its guns for years, continuing to sell only a Cosmic Carbone clincher series with an aluminum brake track and semi-structural carbon fairing, as well as the tubular-only Ultimate. The PR line every time we’ve asked about a full-carbon clincher as been “we can’t make one that meets our standards.”
In a way, they still can’t, at least not by our usual definition of a carbon clincher. But apparently neither can anyone else, sending Mavic in a wholly distinctive direction.
The all-new Cosmic Carbone 40C isn’t a full-carbon clincher as we know it; it’s another hybrid. But unlike the previous Cosmic Carbone versions, the new wheels no longer use a heavy aluminum brake track. The 40C features an aluminum core, one that is far too flimsy to be used as a rim on its own, and wraps it with carbon. It is intended to solve the heat and other issues that have always been associated with carbon clinchers, while adding minimal weight.
The safe route
Carbon clinchers can provide vastly superior aerodynamics, the sort unavailable to an all-aluminum wheel without a massive weight penalty or the hassle of gluing tubulars. Plus, they look exceptional. Between these few factors we find the motivation for the their ever-increasing market share.
But they also have problems, and always have. A more detailed evaluation of the genre as a whole was published on Velonews.com, but the rundown is simple: carbon does not move heat well, resulting in overheating, nor does it brake well, resulting in excessive and unwanted forward motion, particularly in wet conditions. In addition to these safety concerns, carbon clinchers, due to various design constraints, are always significantly heavier than their tubular counterparts, and are often heavier than all-aluminum wheels, yet cost two to three times more. The consumer value is often just not there.
Like every other wheel company on earth, Mavic wanted to solve these problems. They took a particularly slow approach to doing so, holding out for years until the company could finally create “the first reliable carbon clincher,” as road product manager Maxime Brunand put it. At first glance (and that’s a very important qualifier), they may have done just that.