There are certain fundamental bike-related decisions we've all faced: Shimano or Campy; Fizik or Selle Italia; Continental or Vittoria? No decision, though, seems to cause the consternation of the power-training neophyte: Power Tap or SRM? There are a dozen arguments for choosing either brand. But, historically, one factor swayed more people over to SRM than any other: If you're keen on time trials, a Power Tap is of no use. Why? Because until now, the Power Tap was unavailable in a disc wheel, and no piece of equipment is so essential to a motivated time trialist as a disc.

But, finally, after years of experimentation and testing Zipp and Cycleops have finally come together to produce the definitive solution: The Sub-9 Lenticular/Power Tap 2.4 disc wheel. In every detail it's identical to Zipp's standard Sub-9 Lenticular disc. It has the same bulging rim shape, the same dimples, and the same promise of negative drag. But instead of the standard Zipp hub, it instead has Power Tap 2.4 wireless powermeter hub internals, so it serves as a full-on powermeter.

This is the exact wheel used by Team Slipstream-Chipotle for time trialing, and it's thoroughly suited for the task since it weighs only 100g more than the standard Sub-9 disc, totaling 1100g. Like the standard Sub-9, it's available in 700c tubular only. It's available for Shimano/SRAM and for Campagnolo. Since Zipp manufactures the hub itself, you can upgrade it to ceramic bearings. The disc comes with an angled valve adapter so that the tire can be pumped up and six Zipp "jersey" patches for covering the valve cutout. The disc comes complete with Power Tuned Agent 7.0 Software which is Mac and PC compatible, computer head and harness and the USB interface so you can download the data from your handlebar-mounted computer to your desktop.