Automotive

If you want to know what Speed Constant is, then here is an article on Calculating Engine RPM from Motorcycle Speed.

Metric: 165/80-14 (Ignore the rest). Here, the first number 165 is the Width. This means the tire is 165 mm wide. After the slash, we have the height.

Calculating Speed Constant for Motorcycles, with which, if multiplied with speed gives RPM, or if divided from RPM gives speed.