Uniroyal RainSport 5 is a summer tyre made in total of 124 sizes, ranging from R15 to R15 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 225/45 R18 is 40mm wider than the narrowest dimension (185) and 70mm narrower than the widest one (295). This tyre profile of 45 means the sidewall height of the tyre is 45% of the tyre width (225mm), which results in 101.25mm sidewall height. In 225/45 R18, there is only one possible speed index for Uniroyal RainSport 5 - "Y", which is good for speeds up to 300 km/h. In 225/45 R18, RainSport 5 usually competes against Ecsta PS71, which is a tyre from Kumho with a rating of 68%, compared to 64% of the Uniroyal in question. Latest test in 225/45 R18 was held by Autobild in 2023, where RainSport 5 received rating "Satisfactory" and finished on the 17. place. It was tested on a BMW 3.
