Sigma Bike

I have the education, but they juice ..... I heard about marking tires and rotate tires full, then measure the distance, but did you convert to the metric system?? you need a period of four digits .... Aid

Here is a link to a page with all the numbers you will need calibration.

http://www.sheldonbrown.com/cyclecompute ...

I would go with the link Jay provided.

What happens is that the circumference must be entered in millimeters (mm). 25.4 mm to an inch.

The circumference of a wheel 23mm 700c is usually 2096 but it varies a bit depending on the rate of inflation (pressure) and the tire manufacturer.

If you get the circumference to within 3 / 4 inch, you'll be more than 99%. Many people try to get a mm, but only because they can.

A timer car is rarely exact same 98%. So do not worry too much.