Bridgestone Potenza Race 235/40 R18

Bridgestone Potenza Race is a summer tyre made in total of 24 sizes, ranging from R17 to R17 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 235/40 R18 is 10mm wider than the narrowest dimension (225) and 90mm narrower than the widest one (325). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (235mm), which results in 94mm sidewall height.