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how to adjust speedometer for bigger tires
How to adjust speedometer for bigger tires: When changing the wheel size, the flat ratio of the tire must be reduced accordingly, so that the size of the tire can be close to the original size, and the speedometer will not be affected. For example, the tire of 195/55/15 uses a 15-inch wheel, and the size of the wheel is replaced with a 16-inch wheel. The tire size close to it is 195/50/16. It can be seen that increasing the wheel size with the same tire width must reduce the aspect ratio accordingly.
The speedometer calculates the speed according to the unit speed pulse given by the output shaft of the variable box. There are two situations after changing the big wheel:
1. Increase the wheel hub, the tire diameter and circumference have not changed, and the speed per hour has not changed.
2. Increase the wheel hub, and at the same time change the diameter and circumference of the tire, when it is larger than the original tire size, 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 less than the speed displayed by the instrument. Note: (When the vehicle is equipped with ABS, changing the tire size will affect the response speed and effect of the ABS, causing potential safety hazards).
Note:Enlarged wheel size classification:
Increase the wheel hub, the tire diameter and circumference have not changed, and the speed has not changed. Increase the wheel hub and change the tire diameter and circumference at the same time. When the tire size is larger than the original tire size, 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 less than the speed displayed by the instrument.
Precautions for increasing wheel size:
It is not advisable to modify the wheel hub to 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 feeling of the ground will be more obvious, which will greatly reduce the comfort of passengers when passing through uneven roads. 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 the replacement of the big wheel, so it is necessary to check frequently to avoid the occurrence of traffic accidents. You need to pay attention when modifying the wheels. Only the wheels of the same size can pass the annual inspection. If the wheels are not the same size, they will not pass the annual inspection.
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