Specialized factory team rider bikes — both 26- and 29-inch wheel varieties — were fitted with prototype carbon rims for this year's races at the Sea Otter Classic. Todd Wells won Saturday’s short track on the 29-inch version.
Specialized global marketing manager Nic Sims wouldn't say much about the new wheels except "They're Project Black!". To our eyes, however, they look like a composite version of the company's existing Roval aluminum models.
Outer rim profile is similar with a roughly U-shaped cross-section and a flat inner wall supporting externally accessible alloy nipples. Given the relatively short sidewalls, we're guessing these new rims are also tubeless-compatible (with tape and sealant) similar to the NoTubes-like system Roval currently uses for easy conversions.
Sauser's 26-inch rim sported a glossy finish and external nipples. Chances are there's a tubeless-compatible rim bed hidden underneath there, similar to the one used on the company's current aluminum rims.
The aluminum hubs look to be standard Roval fare with straight-pull spokes – laced in a 2:1 pattern up front for more even tension between the two sides – a carbon fiber center section up front, and interchangeable end caps to maximize surface area contact on compatible forks.
The front hub bears the usual Roval trademarks, including 2:1 spoke lacing, a carbon fiber center section, and straight-pull spokes.
In spite of the carbon construction, we expect these to be lighter than their aluminum counterparts but not dramatically so as the alloy rims were already very light. However, we are also expecting more significant jumps in stiffness and durability when these are eventually officially announced – we're guessing later this summer when Specialized holds its 2011 global launch.