All bicycle tires are tested on a rolling resistance test machine with a 77 cm drum and a DC electric motor. The drum is covered with diamond plate to simulate an average road surface.
Measurements are taken with an Arduino microcontroller equipped with custom software and hardware. Our setup calculates the average power required to keep the drum at a set speed for a period of 30 seconds. Using our custom setup to measure input power results in a very accurate measurement.
After a warm-up period of 30 minutes, three measurements are taken. We then calculate the average of these three runs. After a correction for the electric motor efficiency and subtraction of the power required to spin the drum and wheel to the set speed, the result is the rolling resistance of the tire.
To guarantee our setup delivers consistent results over an infinite time period, We've built an ingenious calibration tool that's used to calibrate our machine to known values.
Some facts about our "standard" test:
- 77 cm drum diameter.
- Standard test drum speed of 200 RPM which translates to a speed of 18 mph / 28.8 km/h.
- Diamond plate drum surface.
- 42.5 kg load.
- Butyl tube.
- Computerized measurements.
- Controlled temperature between 21.5-22.5 °C / 70-73 °F.
For a detailed explanation of rolling resistance check Wikipedia.
Puncture Resistance Test
The puncture resistance test is performed with a 1 mm thick, steel needle to which weight can be added. This needle gets positioned on top of the tire, at the center of the tread. More weight gets added until it punctures the tire. This test is done five times. A score of 10 in the puncture test means it takes twice as much force to puncture when compared to a score of 5.