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The tire size designation, commonly found on the sidewall of a tire, provides important information about the tire’s dimensions and characteristics. Here’s a breakdown of the components in a typical tire size designation, using the example “P205/60R15”:
- Letter Prefix (e.g., P): Indicates the type of vehicle for which the tire is intended. Common prefixes include:
- Tire Width (e.g., 205): Represents the width of the tire in millimeters, measured from sidewall to sidewall when the tire is mounted and inflated to the recommended pressure.
- Aspect Ratio (e.g., 60): Indicates the aspect ratio or profile of the tire, which is the ratio of the tire’s height to its width. In this example, the height of the tire sidewall is 60% of the tire’s width.
- Construction Type (e.g., R): Denotes the construction type of the tire. Common construction types include:
- R: Radial ply construction, where the tire’s plies run radially from bead to bead across the tire.
- D: Diagonal or bias ply construction, where the tire’s plies run diagonally across the tire from bead to bead.
- B: Belted bias construction, which combines bias and belt construction.
- Rim Diameter (e.g., 15): Specifies the diameter of the wheel rim in inches onto which the tire is mounted.
Using this information, a tire size designation provides valuable details about the tire’s dimensions, construction, and compatibility with different vehicles. It’s essential to select tires that match the manufacturer’s recommendations for your vehicle to ensure proper performance, handling, and safety.
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