Firestone Roadhawk 255/55 R18

Firestone Roadhawk is a summer tyre made in total of 165 sizes, ranging from R15 to R15 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 255/55 R18 is 90mm wider than the narrowest dimension (165) and 40mm narrower than the widest one (295). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (255mm), which results in 140.25mm sidewall height. In 255/55 R18, Roadhawk usually competes against Dynaxer HP5, which is a tyre from Kleber with a rating of 51%, compared to 52% of the Firestone in question.