Polymer files #3

Aero Testing with ZeroDrag Lab

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Polymer Workshop® has been evaluated by ZeroDrag Lab, a Copenhagen-based aero optimization firm, whom conducted a thorough Aero Testing. This protocol rigorously evaluated our Enhance 50:52 wheelset against top market competitors, underlining the performance of aerodynamics.

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They tested the Polymer Workshop® Enhance 50:52 wheels on an aero road bike, simulating a hoods position. The bike was equipped with a round bottle on the down tube and Pirelli ZERO™ Race TLR 30mm tires, with tire pressures adjusted to the individual wheelsets rim width.

The testing ground involved a flat 3 km stretch of tarmac. A consistent power output, equivalent to 40 km/h in calm conditions, was maintained while riding back and forth along the stretch.

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Instrumentation and Measurement

For precise measurements, they employed specialized tools. A custom aero sensor was used to measure ground speed, environmental variables (air speed, wind direction), and air density. Assioma Favero powermeter pedals accurately gauged the power input by the rider.

CdA Calculation

Utilizing the gathered data, including measured power, ground speed, air speed, air density, and the total mass of the system, along with a fixed rolling resistance coefficient, they calculated the CdA (aerodynamic drag coefficient) for each setup.

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Repeatability and Comparison

To validate the data, the Polymer Workshop® Enhance 50:52 wheelset underwent dual testing - first and last. This practice showed a minor difference of 1.6W at 40 km/h or 0.6%, emphasizing the protocol’s accuracy.

Wind and Yaw Angles

The test scenario featured a moderate average yaw angle of around 4°, a common real-world occurrence. Wind conditions were also analyzed, averaging around 3.5 m/s with gusts up to 5.4 m/s, at an approximate 40° angle to the test stretch. Notably, at higher yaw angles, wheelsets with wider rim profiles like the Polymer Workshop® Enhance 50:52 showcase advantages, resulting in reduced aerodynamic drag.

The Verdict

In this Aero Testing, the Polymer Workshop® Enhance 50:52 wheelset is on the same aerodynamic level as the Princeton Peak 4550 and Roval Rapid CLX II.

The results indicated that on average the Peak 4550 was 0.4W faster corresponding to 2 seconds gained over 40 km, while the Roval was 0.9W slower corresponding to 4 seconds lost over 40 km. However, this is within the margin of error of the testing and suggests these wheelsets are very close in aerodynamic performance.

These results are achieved and validated by ZeroDrag Lab.