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Tire sizes are written in a standardized format that tells you the width, height, and diameter of the Tire Size. The format is as follows:
Width/Aspect Ratio/Rim Diameter/Load Index/Speed Rating
Width is measured in millimeters and refers to the distance from one sidewall to the other. For example, a tire with a width of 225 millimeters would be written as “225.”
Aspect Ratio is a percentage that tells you how tall the tire is compared to its width. For example, a tire with an aspect ratio of 70 would be written as “70.” This means that the tire is 70% as tall as it is wide.
Rim Diameter is measured in inches and refers to the Tire Size of the wheel that the tire fits on. For example, a tire with a rim diameter of 16 inches would be written as “16.”
Load Index is a number that tells you how much weight the tire can carry. The load index is assigned by the Tire and Rim Association (TRA). For example, a tire with a load index of 91 can carry up to 1,385 pounds.
Speed Rating is a letter that tells you the maximum speed at which the tire can be safely operated. The speed ratings are assigned by the TRA and range from A (the slowest) to Z (the fastest). For example, a tire with a speed rating of S can be safely operated at speeds up to 112 mph.
Here is an example of a tire size:
P225/70R16 91S
This tire has a width of 225 millimeters, an aspect ratio of 70, a rim diameter of 16 inches, a load index of 91, and a speed rating of S.
It is important to note that tire sizes can vary depending on the type of vehicle. For example, light trucks and SUVs typically have wider tires than cars. It is also important to check your vehicle’s owner’s manual to find the correct Tire Size for your vehicle.
“This article was written by Bard, a large language model from Google AI.”