Gear inches

Under the unfolding of expiry or length means the length of the route, which covered a bicycle through a revolution of the pedal cranks.

Calculation

To calculate the unfolding one must know the circumference of the wheel and the translations of both sprockets and a possibly existing internal gear hub.

The circumference of a wheel U with 28 inch diameter is, for example,

The ratio i from one chainring with 44 teeth and a pinion with 19 teeth is

The unfolding l then

One turn of the cranks per second travel speed results so v of