How to Calculate Rim Speed
- 1). Measure the distance from the center of the rim to the outer edge with your tape measure. You now have the radius of the rim.
- 2). Multiply the radius by pi and double the result to get the circumference of the rim.
- 3). Measure the rim's current revolutions per minute with the RPM gauge.
- 4). Multiply the circumference measured in Step 2 by the RPM measured in Step 3 to get the rim speed.
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