Care of Tires
Tires, like the engine or other parts of a car, require a reasonable amount of attention and care if the owner expects to secure the best results. There have been many refinements in the construction of tires and those built with quality for a base are very dependable; in fact, so much confidence is ordinarily placed in the tire equipment, sometimes unconsciously, that the tires do not receive the frequent inspection and attention that is considered necessary for the car. Should the engine overheat and the bearings burn out, due to lack of lubrication, the result would not be considered an evidence of mechanical error; it would be properly chargeable to oversight and neglect. It is not always possible to avoid stones and other sharp objects, ruts and severe road conditions, and we shall not attempt to define certain rules or offer impracticable suggestions to be followed in using tires, says the Firestone Tire and Rubber Company’s expert on tires.
The application, care and usage of tires are necessary things to consider but it is essential to good service that the correct type and size be adopted. Car construction, power, lateral strains and traction strains to the tires must be kept in mind when deciding upon diameter and cross section of tire equipment, but the weight of car is probably the most important thing. The weight of the car can be ascertained by running the front half of it on platform scales, then rear half, and the weight carried by each tire will be one-half of the respective amounts. Middle of wheel base will be the weight dividing point between the front and rear halves of car. The approach to the scales should be level and, if reasonable care is exercised, the total of the two operations will be within twenty or thirty pounds of the weight of the car when all of it is upon the scales. Weight and distribution of car, power, gear ratio, speed and other points are considered by the car engineers and tire makers in determining the tire sizes necessary for equipment. It will be appreciated, however, that the usage of cars will vary on account of road conditions, drivers and for other reasons. Therefore it is reasonable to expect some trouble from the tires on a small percentage of cars, even though the equipment on a majority of the cars proves satisfactory in every respect. When tires are loaded beyond their normal carrying capacity, the fabric is not only strained but develops more hinging action and heat at ends of tread. The materials employed in the manufacture of tires are limited in strength, like other articles, and when taxed beyond that point will not be efficient. Oversize tires were primarily designed for exceptional and hard service but have come into general favor because of extra strength, easier riding cushion and longer mileage, in fact, experienced car owners specify the oversize tires, in many instances for original equipment of new cars. The resiliency of larger tires reduces the traction slippage on rear wheels, adds to comfort and lessens vibration to the mechanism of the car. When oversize tires are placed on front wheels that were originally equipped with regular size tires, the over-all diameter will be increased approximately one inch and the speedometer should be adjusted, otherwise the mileage recorded will be less than that actually traveled. There is not enough added weight in oversize tires to affect transmission or differential or make any objectionable difference in the power. The advantages of oversize tires, without the inconvenience or expense of changing wheel equipment, are features which mean much to the user.