Dunlop Sportmax Roadsmart IV 180/55 R17

Dunlop Sportmax Roadsmart IV is a allround tyre made in total of 9 sizes, ranging from R17 to R17 - this particular dimension is R17, which means it fits to a 17 inch/431.8mm diameter wheel. 180/55 R17 is 30mm wider than the narrowest dimension (150) and -10mm narrower than the widest one (170). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (180mm), which results in 99mm sidewall height.