Practical guide

How to Measure Loaded Bicycle Wheel Rollout

Measure the actual distance traveled per wheel revolution for more accurate gear-inch and cadence calculations.

Loaded rollout is the distance the bicycle travels during one complete wheel revolution. It captures the mounted tyre’s actual effective circumference better than a nominal tyre label.

Rollout method

1. Inflate the tyre to the setup you intend to compare, staying within tyre and rim limits.
2. Put the bicycle on level ground with normal load.
3. Mark the tyre at the ground contact point and mark the starting point on the floor.
4. Roll forward in a straight line until the tyre mark returns to the ground after one full revolution.
5. Mark the end point and measure between floor marks in millimetres.
6. Repeat several times and use the average if the results differ.

Do not estimate rollout from the rim’s bead-seat diameter alone. Tyre casing, mounted width, tread, inflation and load contribute to outside rolling size.

Using the measurement

Gear-development and cadence arithmetic can use rollout to derive effective diameter and distance per wheel revolution before applying the tooth ratio. Those specialist calculators remain out of the search index until their required cycling review is recorded.

These calculations assume no tyre slip and conventional external gearing. They are comparison tools, not speed or cadence recommendations.