The aspect ratio, or profile, refers to the height of the sidewall as a % of the section width. In our example, 55 means the height is equal to 55% of the 195mm width. The bigger the aspect ratio, the bigger the sidewall will be. Tyre size explained Tyre dimensions. Width: The section width of your tyre in millimetres, from the inner sidewall to the outer sidewall. Example: 195mm. Aspect Ratio: The height of your tyre from the base of the tread to the rim, as a percentage of the tread width. Low profile tyres have smaller aspect ratios. The most basic information that you'll find on a tire's sidewall is related to its size. This is normally written as 185/65R15, for example, though you'll sometimes see "P" (for passenger cars) The set of numbers straight after the tyre width refers to the thickness of the tyre wall (or aspect ratio), which is a percentage of the width. So, in this case, 55 would have a height equal to 55% of the tyre's width. This number is often referred to as the tyre profile. Tyre construction Tire size can be defined as a collection of numbers and letters that describe tire type, width, sidewall height, and wheel diameter — alongside other information. An example of a common tire size is as follows: P225/65R17. The tire size for your vehicle and wheels can be found in two places: The sidewall of your tire. QmZNqny.

what does the size mean on a tire