november cycles is developing new rim. real independent development in a2 windtunnel.
unlike zipp they are quite honest on testing/reporting at different speed levels.
You would have a great point there if we hadn't addressed this back in February of 2007 (this test was over Valentine's Day, I know because my wife was not so happy).http://www.zipp.com/_media/pdfs/technol ... _speed.pdf
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It's all very well accepted that in the Reynolds Number arena in which bicycle wheels operate it's a safe assumption that CdA is essentially constant with a change in velocity. Given that, the formulas for drag force and power then scale with V^2 and V^3, respectively. Therefore, it's trivial to scale data up or down from a known velocity to a desired velocity (again, this is a bit of an oversimplification but applicable in our area).
We had been saying this for some time, but as we still see, some people have a difficult time believing this, so we actually took the data at both 20 mph and 30 mph and then compared it to the results of scaling the 30 mph data down to 20 mph. Anyone so inclined can take the data we (and others) release given 30 mph velocity and scale to what they deem an appropriate velocity.