iBike iAero Generation III, Справочное руководство

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Copyright Velocomp LLP 2008-2010
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UNDERSTANDING HOW TO USE YOUR IAERO
FOR CdA MEASUREMENTS
The ability to measure aerodynamic drag while riding is a revolutionary new
feature made possible by the iAero. Please take a few moments to read this
section so you can learn how the iAero works. Understanding how the iAero
works will help you tremendously as you use your iAero to improve your cycling
performance.
When you perform the initial coast-downs and calibration ride, the iAero and the iBike
software together determine your “baseline” aerodynamic and frictional drag coefficients.
These coefficients characterize your “normal” riding position and “normal” road/bike
condition. These baseline aerodynamic and frictional drag coefficients are stored in the
iAero.
What’s new in the iAero is the ability to explore changes in your ride position, equipment,
and clothing,
and to see their effect on your baseline aerodynamic drag coefficient .
Suppose your baseline aerodynamic drag coefficient is 0.28 (this number is determined in
your calibration ride and is displayed in each of your ride files): by how much will your CdA
decrease if you go into a tuck? What penalty (higher CdA) do you pay if you put on a
jacket?
These are the kinds of questions any iAero can answer with ease.
The iAero provides two kinds of CdA measurements: Snapshot CdA™, and Continuous
CdA™. Snapshot CdA measurements are available from
any iAero, but Continuous CdA
measurements require the use of a direct force power meter (DFPM) .
The following sections will explain each kind of CdA measurement in detail.