Quote:
Originally Posted by m_sasso
Now they need to combine wind resistance in these tests to get a partial picture of real world performance!
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There can often be more variables in aerodynamic testing than rolling resistance testing, so when throw tires into the equation it becomes even more complicated. But that hasn't stopped some groups from trying.
For example, Flo Cycling, a maker of aero wheels, ran some tests on a variety of different tires to find the best tire for a combination of aerodynamics and tire rolling resistance. However, they only used one model of their wheels, and the results of their test may not be applicable to other wheels. Still, their test and results are interesting (the test and results can be found
here).
One interesting thing from this test is that the highest aerodynamic drag power with any of the tires tested was only about half the lowest rolling resistance drag power of any of the tires tested - i.e., rolling resistance is a much bigger factor in wheel performance than aero drag. When Flo combined aero + rolling drag, the best combination was not the one with the lowest air resistance, it was the one with the lowest rolling resistance tire (in fact, that combination actually had the 11th best aero drag out of 20).
Also of note is that Flo used a speed of 21.75 mph for the test. While many companies report wind tunnel results at much higher speeds (30 mph is a typical speed), and therefore exaggerate aero benefits, the Flo results are reported for a speed that probably more closely matches most people's actual speeds. In at least one regard, Flo's results confirm my own personal experiences - I can barely detect speed differences between aero and non-aero wheels, but I can easily detect speed differences between high and low rolling resistance tires.