What Are the Size Specifications of Tires?
3 Answers
Common tire model specifications typically include 185/65-R14, 185/65-R15, and 205/55-R16. Taking 195/55R15 as an example: 195 is the section width, 55 is the aspect ratio, R stands for radial tire, and 15 is the inner diameter of the tire, which is also the diameter of the wheel hub. Below are the functions of car tires: 1. Support the entire weight of the vehicle: Support the entire weight of the vehicle, bear the load of the car, and transmit forces and moments in other directions. 2. Transmit traction and braking torque: Transmit traction and braking torque to ensure good adhesion between the wheel and the road surface, improving the car's power, braking, and passability; work together with the car suspension to mitigate impacts during driving and dampen resulting vibrations. 3. Prevent damage to car components: Prevent car components from experiencing severe vibrations and early damage, adapt to the vehicle's high-speed performance, reduce driving noise, and ensure driving safety, handling stability, comfort, and energy efficiency.
Tire size is like shoe size – choosing the wrong one makes driving uncomfortable. The most common format is 205/55R16: 205 indicates the tire width in millimeters, with larger numbers meaning wider tires and better grip; 55 is the aspect ratio, representing the sidewall height as a percentage of the width, with sports cars often using thin tires below 40; R stands for radial construction; and 16 is the wheel diameter in inches. When replacing tires, these three parameters must match the original specifications, or they may rub against the wheel arches or cause inaccurate speedometer readings. Additionally, the last alphanumeric combination, such as 91V, indicates the load index (91 = max load of 615 kg) and speed rating (V = max safe speed of 240 km/h). When switching to winter tires, check for the snowflake symbol on the sidewall – safety first.
Friends who are into car modifications pay the most attention to tire specifications, as they directly affect handling. The first number indicates the section width in millimeters—a larger value means better grip but higher fuel consumption. The two-digit aspect ratio in the middle is crucial; lower-profile tires offer sharper steering and less body roll during corners but are more prone to bulging. The number after 'R' denotes the rim size, determining the compatible wheel diameter. Lastly, the speed rating (e.g., H, V) must match the engine's performance. Wide tires paired with large rims certainly look stylish, but the overall diameter change must be calculated to avoid rubbing against the fenders. Some track enthusiasts deliberately reduce the aspect ratio for improved road feedback, but for daily driving, it's best not to go too extreme.
