Zipp

Super 9 Disc Carbon Rear Wheel - Clincher

Tubulars have long been the go-to for any serious racing, and anything necessitating a full disc rear wheel was certainly serious racing. But when Zipp started working on a clincher version, it found that the shape of the clincher tire, combined with the brake track angle, made for a more aerodynamic wheel than the tubular version. With this discovered, Zipp set about making a fast wheel faster in the way only it can.

The dimples you see are the key — they create a false boundary layer over the wheel that’s inherently smoother than any physical surface could be, so air moves over the wheels as though they’re almost not there. The dimples also allowed Zipp’s engineers to optimize what air does at various yaw angles, since you’re rarely racing on a perfectly still day.