Tyre Model and Specification Chart

The tyre model and specification chart provides essential details to help you choose the right tyres for your vehicle. Key information includes tyre size (e.g., 205/55 R16), load index, speed rating (e.g., V for 149 mph), tread pattern, and seasonal suitability (summer, winter, all-season).

1. Tyre size: The first number (205) is the width in millimetres, the second (55) is the aspect ratio (sidewall height as a percentage of width), and R16 indicates a radial construction with a 16-inch rim diameter.
2. Load index: A numerical code (e.g., 91) representing the maximum weight the tyre can support.
3. Speed rating: A letter (e.g., H, V, W) denoting the tyre’s maximum safe speed.
4. Tread pattern: Affects grip, noise, and water dispersion. Directional tyres (like those on a Ford Focus ST) excel in wet conditions, while asymmetrical tyres (common on BMWs) balance dry and wet performance.
5. Seasonal markings: Look for a snowflake symbol (winter tyres) or "M+S" (mud and snow). All-season tyres (e.g., Michelin CrossClimate) are a compromise for milder climates.

Always match tyres to your vehicle’s manual and driving needs. For example, a Tesla Model 3 may require low-rolling-resistance tyres for efficiency, while a Vauxhall Corsa might prioritise affordability and durability.

From a safety perspective, the tyre specification chart is critical. Incorrect tyres can compromise braking, handling, and fuel efficiency. For instance, a tyre with a lower speed rating than your car’s capability may overheat at high speeds. Similarly, an incorrect load index risks tyre failure under heavy loads. Always cross-check the chart with your vehicle’s manual and driving conditions.

Automotive tyre specification parameters include: section width (mm), aspect ratio (%), tyre type code, rim diameter (inches), load index (permissible load mass code), and permissible speed code.

1. Section width and rim diameter reference table:
2. Load index reference table:
3. Tyre speed rating reference table:

Assuming the tyre specification is 195/55/R16 85V, the model specifications represent the following information:

1. 195 – refers to the tyre width of 195mm.
2. 55 – refers to the aspect ratio, meaning the section height is 55% of the width.
3. R – indicates that the tyre is a radial tyre (the inner layer of this tyre is constructed using the radial method).
4. 15 – refers to the rim diameter of 15 inches.
5. 85 – the load index 85 represents a maximum load capacity of 515 kg, with four tyres totalling 515×4=2060 kg.
6. V – indicates a speed rating of 240 km/h.