[lagadu]

Tyre sizes in Europe are an ungodly mix: 295/30R20 for example measures as:

295mm tyre width, sidewall height is 30% of the width and the wheel it fits in is 20 inches (can't recall whether it's 20 inch radius or diameter).

[sib]

Diameter...

(Is there anywhere that doesn't use this mix of measures for tire sizes [tyre syzes]?)