In recent years there has been much talk of the 650b wheel size, but very little of 650c. Zipp hopes to change that with the introduction of a 650c 404 Firecrest Carbon Clincher.
Australian pro triathlete Mirinda Carfrae, who stands 1.6m/5-foot-3, rode a prototype pair of the smaller road wheels at the 2012 Ironman world championships in Kona last fall.
Carfrae's Kona bike with 650c prototype 404s
The 650c size is fairly rare now, with virtually all stock road, time trial and triathlon bikes being made for 700c wheels. But Zipp is betting that smaller riders still appreciate and deserve proportional frames without compromise in geometry
"As it is now for most bikes, small frames have their geometry adjusted for 700c wheels," said Zipp technical PR manager David Ripley. "The further you rake the steering axis (by angling the fork away from the frame), the longer that lever gets, and the more reactive the steerer is. The end result is not a bike with great handling. Short people need smaller bikes. And smaller bikes need smaller wheels."
Smaller wheels allow for proper geometry on smaller bikes, Zipp says
Zipp's 650c 404 Firecrest Carbon Clincher features a 58mm-deep rim that is 24.73mm wide at the brake track and 27.5mm across at its widest point. The 10- and 11-speed compatible wheel features Zipp's toroidal shape and dimpled profile.
The 1,465g wheelset will sell for $2,725 (£1,740).
In related news, Zipp also announced a new carbon aerobar, the Vuka Stealth, that features a host of adjustability in an integrated bar/stem design.