Rush wrote:Ok so I've drawn some pretty lines around the rim profiles of the A23 (left), HED C2 (middle) and Bikehubstore C472 (right)...
Rush; all that work and you only took into account about 40-45% of the equation! I would suspect the Bikehubstore probably has a better advantage over the Hed when the rim is the leading edge(particularly at yaw) and much less so as a trailing edge as you depict.
Anyways, I don't think Hed themselves think that their profile is particularly aerodynamic. I think they merely mean to say that a 23mm wide rim's walls will better match the 23mm wide tires people run anyways. You must remember when they released the 23mm wide C2 rim something like 4-6 years ago they were just about the first to make a 23mm wide road racing rim. Maybe this just demonstrates they are due for an overhaul.