Michelin Pilot Sport 4 S is a summer tyre made in total of 246 sizes, ranging from R17 to R17 - this particular dimension is R21, which means it fits to a 21 inch/533.4mm diameter wheel. 275/30 R21 is 50mm wider than the narrowest dimension (225) and 50mm narrower than the widest one (325). This tyre profile of 30 means the sidewall height of the tyre is 30% of the tyre width (275mm), which results in 82.5mm sidewall height. In
275/30 R21, Pilot Sport 4 S usually competes against
Ventus Evo, which is a tyre from
Hankook with a rating of 99%, compared to 97% of the
Michelin in question.