What is the rolling radius of a tire?
2 Answers
The rolling radius of a tire needs to be calculated based on the tire model. For example, the rolling radius of a 185/65-R15 tire is approximately 310.75mm, calculated using the formula (381 + 120.25 × 2) / 2 = 310.75mm. Below is some information about tires: 1. Introduction: A tire is a circular elastic rubber product mounted on various vehicles or machinery to roll on the ground. It is usually installed on a metal rim to support the vehicle body, absorb external shocks, ensure contact with the road surface, and maintain driving performance. 2. Required properties: Tires are often used under complex and demanding conditions, enduring various deformations, loads, forces, and high/low temperatures during operation. Therefore, they must have high load-bearing capacity, traction performance, and shock absorption. Additionally, they need to exhibit high wear resistance, flex resistance, and low rolling resistance with minimal heat generation.
To be honest, the concept of tire rolling radius sounds a bit technical, but simply put, it's the actual radius of the tire when it's rolling. Why does it matter? It affects every aspect of your car, like the accuracy of the speedometer—I’ve noticed discrepancies when driving on highways. The rolling radius isn’t the same as the nominal radius marked on the tire sidewall because the tire flattens slightly under the car’s weight, especially under heavy loads or low pressure, reducing the radius. At high speeds, centrifugal force can cause it to expand a bit, but only to a limited extent. Worn-out tires show more noticeable radius changes, leading to unstable steering or increased fuel consumption. I often advise friends to check tire pressure regularly—don’t overinflate or underinflate, but keep it close to the recommended value. When tire pressure is optimal, the rolling radius remains stable, improving handling, reducing the risk of losing control, and even saving some fuel. Ignoring this poses serious safety risks, like skidding during sharp turns, especially on wet roads. A little maintenance can prevent accidents.
