English 
how to correct speedometer for larger tires
The speedometer needs to be adjusted when the hub size increases. Increase the classification of wheel hub size: increase the size of the wheel hub, the diameter and circumference of the tire have not changed, and the speed per hour has not changed. When the wheel hub is enlarged and the tire diameter and circumference are changed, the actual speed of the vehicle will be greater than the speed displayed on the instrument at the same speed. When it is less than the original tire specification, the actual speed of the vehicle is less than the speed displayed on the instrument. Precautions for increasing the size of the wheel hub: refitting the wheel hub should not be too wide. The larger the wheel hub, the thinner the tire will be in order to maintain the flat ratio of the vehicle, and the more obvious the feeling on the ground will be. When passing through uneven road sections, the comfort of passengers will be greatly reduced. It is necessary to pay attention to the tire wear of the vehicle from time to time, because the tire wear will be aggravated after replacing the large wheel hub. Therefore, it is necessary to check frequently to avoid traffic accidents. Attention should be paid to refitting the wheel hub. Only refitting the wheel hub of the same size can pass the annual inspection. If it is not the wheel hub of the same size, it cannot pass the annual inspection.
The vehicle speed displayed by the speedometer is calculated by the wheel axle speed and the original wheel diameter. If the tire size is increased, the speedometer displays 80KM, and the actual vehicle speed should be 80 times the actual diameter/original tire diameter.
The impact of tire size on the car is:
1. The resistance torque of driving under the same working condition will change, that is, the acceleration and climbing force of the vehicle will decrease, but the extreme speed of the vehicle will increase in theory.
2. The run-up and run-down travel of the wheel becomes smaller, and the suspension system (shock absorption) needs to be strengthened.
3. The actual speed is slightly higher than the displayed speed.
The enlarged hub will not affect the speedometer. The following is related introduction: speedometer introduction: the speedometer calculates the speed according to the unit speed pulse given by the transmission output shaft. What happens after replacing the big wheel hub: enlarge the wheel hub, the diameter and circumference of the tire have not changed, and the speed has not changed. At the same time, when the wheel hub becomes larger and the tire diameter and circumference change, the actual speed of the vehicle will be greater than the speed displayed by the instrument at the same speed. When it is smaller than the original tire size, the actual speed of the vehicle is lower than the speed displayed by the instrument. Attention (when the vehicle is equipped with ABS, changing the tire size will affect the reaction speed and effect of ABS, causing potential safety hazards).
Get a Quote / Info