For example the explanation for tire size 225/50 R17 94V is:


* 225 means the tires breadth in millimetres (225 mm = about 8.9 inches)


* 50 stands for the tires aspect ratio height to width (the tires height is 50 % of the tires
cross-section breadth)


* R means Radial


* 17 is the tires diameter in inches


* 94 tells about the maximum weight that a tire can accommodate vertically at a given PSI.

For example, the load index 94 means a 1477 pound (or 670 kg) carriage holding.
The bigger the measure is the larger the carrying capacity is.


* V stands for the speed rate, V means constant speeds up to 150 miles/hour

Q = up to 160 km/h = 100 mph
S = 180 km/h = 112 mph
T = 190 km/h = 118 mph
H = 210 km/h = 130 mph
V = 240 km/h = 150 mph
W = 270 km/h = 168 mph
Y = 300 km/h = 186 mph

1 km/h = 0.6214 mph
100 mm = 3.937 inches


If somebody could give the correct offsets for E60?s 16 to 20 inch wheels this post could be added to FAQ?s.

 

There's also Z (in excess of 240km/h = 149 mph).

Z is also combined with W & Y. As Z really means in excess of 149 mph and the W/Y says by how much...

e.g. 245/40ZR18 94Y (186mph)