Kumho Crugen HP91 is a summer tyre made in total of 50 sizes, ranging from R16 to R16 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 235/55 R18 is 20mm wider than the narrowest dimension (215) and 40mm narrower than the widest one (275). This tyre profile of 55 means the sidewall height of the tyre is 55% of the tyre width (235mm), which results in 129.25mm sidewall height. In 235/55 R18, there are 2 possible speed indexes for Kumho Crugen HP91 - "H","V", which are good for speeds up to 210, 240 km/h. In 235/55 R18, Crugen HP91 usually competes against ZEON 4xS Sport, which is a tyre from Cooper with a rating of 36%, compared to 0% of the Kumho in question.