What are tires?
Four roles of tires
1. Support the load of the car
Tires support not only the weight of the vehicle, but also the passengers and luggage.
Tires are equipped with the ability (strength) to support a considerable weight.
2. Communicate the power of the car (run, stop)
A car cannot run or stop without transmitting the driving force and braking force to the road surface.
Tires are greatly involved in starting, accelerating / decelerating, and braking (braking) performance.
2. Communicate the power of the car (run, stop)
A car cannot run or stop without transmitting the driving force and braking force to the road surface.
Tires are greatly involved in starting, accelerating / decelerating, and braking (braking) performance.
4. Relieve the impact
Tires soften the impact from unevenness on the road surface.
The elasticity of air and rubber acts as a cushion, which contributes to a comfortable ride.
Tire knowledge
● How to check the air pressure
The air pressure should not be too low or too high. The air pressure should not be too high or too low. It is dangerous because the tires deteriorate quickly, cause uneven wear, and are easily scratched. Also, the steering wheel may be taken off while driving, and it may affect fuel efficiency, so check the following two points once a month.
1. Adjust the air pressure when the tires are cold.
2. The air pressure specified by the manufacturer is specified near the driver's door opening, so adjust it to the specified air pressure.
● How to tell when to replace a tire
1. Estimated replacement time
The standard mileage for tire replacement is 30,000 to 40,000 km.
Generally, the mileage is used as a guide for tire replacement, but other factors that reduce the tire groove are: ・ Road conditions
・ Tires wear and deteriorate due to various factors such as sudden starts and sudden stops.
Keep in mind the mileage plus, the above items as a factor in reducing the tire groove.
2. Groove depth
Running on the road with the tires when the groove depth is less than 1.6 mm is prohibited by law. In addition, even if there are more than 1.6 mm of grooves left, the more grooves there are, the more likely it is that slip will occur, making it impossible to drive safely.
There is a triangular mark "▲" called a slip sign on the side of the tire, and if the groove of the tire is worn down from this mark, it will be a guideline that it is 1.6 mm or less as stipulated by law.
If your tires are worn out and reach this mark, replace them immediately.
3. crack
It is easy to notice the reduction of the tire groove because it is easy to see, but it seems that many people do not care much about the cracks in the tire. Even if you haven't run that much and have plenty of grooves left, it's very dangerous to wear a deteriorated and cracked tire.
Even if there are still grooves, I am not reluctant to change tires, and cracks can be seen on the side of the tire.
Be sure to replace tires that have been made for a certain period of time before an accident occurs.
● How to read the tire size
The tire size is displayed on the sidewall of the tire, and the notation method differs depending on the type and standard of the tire.
Recently, the display by ISO (International Organization for Standardization) has become the mainstream.
Tire width, flatness, radial, rim diameter, load index, speed symbol (= speed range), etc. are displayed.
Tire Width
Cross-sectional width of the tire. The tire width excluding the letters and decorations on the side. Depending on the tire, it may be mm or inch.
Flattening
It is a numerical value that represents the ratio of the height (H) to the cross-sectional width (W) of the tire.
radial
Indicates that it is a radial tire.
Rim diameter (inch)
Refers to the width of the part of the wheel that incorporates the tire and is expressed in inches.
Load index (LI = load index)
An index that indicates the maximum load capacity that a tire can support under specified conditions.
Speed symbol (= speed range)
A symbol that indicates the maximum speed at which the tire can run under the specified conditions.