Measuring Wheel friction drag and/or tire rolling resistance

[Brodirt]

Is it as simple as follows to do so?
1. On a given pair of wheels do a few coast downs, a 4 mile ride and set up a profile.
2. Use same tires on a 2nd pair of wheels and do the same coast downs and 4 mile ride, and set up another profile.
3. Compare friction resistance readings between the 2 profiles.

For tires....same routine only use the same wheels and switch tires.

[travispape]

Is it as simple as follows to do so?
1. On a given pair of wheels do a few coast downs, a 4 mile ride and set up a profile.
2. Use same tires on a 2nd pair of wheels and do the same coast downs and 4 mile ride, and set up another profile.
3. Compare friction resistance readings between the 2 profiles.

For tires....same routine only use the same wheels and switch tires.

Yep, that will do it. The calmer the wind conditions, the better the results will be with the coastdowns and since Crr is the more difficult parameter to nail down, it would be good to have fairly clam wind conditions for doing this exercise. Also, it is doubly important to do a good job with the wind offset and tilt calibration procedures before doing calibration rides.