Roymondo:
Bking:
Because its all based on wheel nut pitch circle diameter.
Eg 385 ( width of tyre “face” ,65 Aspect ratio (width to wall height) but the 22.5 is down to the ratio of Pi.The pitch circle diameter of the wheel nuts is 7 inches which multiplied by Pi is (nominal) 22.5 inches or 2pi X r
Complete and utter hogwash. There is no mathematical relationship between the PCD of the wheel nuts and the diameter of the rim (other than the simple fact that the latter must be somewhat larger than the former, in order to accomodate the brakes etc and allow the wheel to be bolted up to the hub). And if it was down to pi, surely the diameter of the rim would be 22", rather than 22.5"? Or have you still not put those batteries in your calculator…?
And so inform us why “22.5” smart ass?