Semperit Speed-Grip 3 is a winter tyre made in total of 49 sizes, ranging from R15 to R15 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 245/45 R18 is 60mm wider than the narrowest dimension (185) and -50mm narrower than the widest one (195). This tyre profile of 45 means the sidewall height of the tyre is 45% of the tyre width (245mm), which results in 110.25mm sidewall height. In 245/45 R18, there is only one possible speed index for Semperit Speed-Grip 3 - "V", which is good for speeds up to 240 km/h. In 245/45 R18, Speed-Grip 3 usually competes against Speed-Grip 5, which is a tyre from Semperit with a rating of 67%, compared to 73% of the Semperit in question. Latest test in 245/45 R18 was held by Autobild in 2020, where Speed-Grip 3 received rating "Good" and finished on the 10. place. It was tested on a BMW 5.
