vehicle > bicycle

Bicyclists almost always express their average speeds in miles-per-hour. However, I think there's value in expressing it in terms of minute miles, as runners do.

This is particularly true in the city, where average speeds will almost NEVER go below a three minute mile (stop lights are a strict limiting factor), and thus, the loss of precision that comes with 1- or 2-minute-miles will never be a concern. When using the bicycle for utilitarian purposes, it's very useful to be able to quickly estimate the amount of time that a particular route will take, since multiplication is much easier to do in your head than division.

minutes per mile mph
3:00 20 mph
4:00 15 mph
5:00 12 mph
6:00 10 mph default average biking speed in city through traffic lights
8:00 7.5 mph
10:00 6 mph conservative estimate for city biking speed, when factoring in possible delays such as active snowfall
12:00 5 mph
20:00 3 mph average walking speed

To convert from mph → minute-miles: