Hankook Ventus Prime3 K125 is a summer tyre made in total of 149 sizes, ranging from R15 to R15 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 225/40 R18 is 40mm wider than the narrowest dimension (185) and -30mm narrower than the widest one (195). This tyre profile of 40 means the sidewall height of the tyre is 40% of the tyre width (225mm), which results in 90mm sidewall height. In 225/40 R18, there is only one possible speed index for Hankook Ventus Prime3 K125 - "W", which is good for speeds up to 270 km/h. In 225/40 R18, Ventus Prime3 K125 usually competes against Cinturato P7, which is a tyre from Pirelli with a rating of 75%, compared to 75% of the Hankook in question.
