The VAST ARRAY OF TIRES available is really fantastic. They range from the tiny doughnuts for lawn mowers to tires for heavy equipment standing twice as tall as a man and costing what the average man earns in three years. And for those few people who have been able to resist the blandishments of Detroit and have chosen to hang on to their 1925 Roosevelt or their 1929 Graham Paige or perhaps their 1931 Model a Ford there is no tire problem.
Not only are those old sizes (4.75 and 5.00X19 and 4.20 and 4.50X21) still available in the original tread and style but they’re a far better tire than the tires which came on the car. Goodyear (and others) turns out tires for antique cars as standard parts of its lines.
Tires have grown in size and changed in shape over the years so that they provide a softer ride and a safer one because more rubber is on the ground than ever before.
They also last longer. Guarantees of 40000 miles of service are available from just about every manufacturer. There are three major types of tire construction today. At the bottom so to speak in tires intended for light service and which are not expended to produce either many miles of tread life or to be used at continuous high speed are those of Bias Angle Construction. Their layers of fabric are laid at angles to one another as they run from one bead to the other.
Next up in quality price and durability are tires built with a Bias Belted Construction. Like the Bias Angle tires they have plies (at least two) of fabric running at an angle from one bead to another and at an angle to the other plies. On top of this are several belt plies beneath the tread material. These belts made of fabric laid in bias to each other run around the circumference of the tire rather than from bead to bead. The idea is that the belted construction keeps the tire tread from squirming as it rolls along the highway. This provides greater traction with less chance of losing it (and skidding) than the Bias Angle tires.
It also enhances tire mileage because when a tire tread squirms it’s very much like being dragged against the rough surface of the road.
Bias belted tires are more expensive to manufacture and consequently cost more money although they give better service.
At the top of the line costing often very large sums of money but giving in turn much greater service better traction and less chance for skidding are Radial Ply Tires. Radial tires are made with two (or more) plies of fabric running at right angles to the bead rather than at an angle to the bead and in bias to each other. Between these plies and the tread are several plies of fabric (sometime of steel) running at right angles to the lower plies and around the circumference of the tire. When they work they work superbly but when they don’t work like the little girl in the story they’re awful.
The tire engineers don’t really know all there is to know about why sometimes steel belted radials don’t work. While writing this book I succumbed to the sincere blandishments of a major tire company’s public relations officer and bought steel belted radial tires for my cars. I have two cars of the same make one two years older than the other both taking the same size tire. On one of the cars the steel belted radials have been everything the factory man said they would be. They provide a sure pleasant ride and I really have been impressed at how far they’ve gone with so little tread wear. On the other, car however they produce a ride like a truck crossing the desert a shimmy in the steering wheel and a demonstrated tendency to wear quickly and unevenly.
With the prestige of his company at stake the factory man has gone to great lengths to blame everything but the tire. The car of course was blamed until finally its toe in and caster and camber and shock absorbers and anything having anything whatever to do with steering were tuned with care and precision normally given only to cars about to run the Daytona 500. When that didn’t fix the problem new tires were installed after having been trued on a tire lathe and balanced to literally sixteenths of an ounce. Since it was conceivable if not very likely that I had gotten eight bad tires in a row four more brand new ones were installed with alt the precision and care of a brain operation and still it shimmied rattled and shook.
Putting a brave smile on his face the factory man finally ordered the installation of the top grade Bias belted tires and the car immediately and since has ridden like a feather. I don’t think he believes it but I was impressed if not with those tires on that car with the eagerness with which he tried to make a bad situation right and with what he wrote on the tires he took off the car.
He returned them to his company laboratory with instructions to take them apart and find out what was wrong with them all twelve of them. It’s surprising that anything goes wrong with tires at all considering the care with which they are made. Most of the major manufacturers make all the material that goes in their tires themselves. If they buy material (cord for example) it is made to their precise specifications while their inspectors watch. There is quality control inspectors at virtually every step of the operation paid to find things wrong with what’s being manufactured.
The tire’s worst enemy is often the car’s owner. The very reliability of tires for so long has made people regard them as something like a light bulb. You know it’s worn out when it doesn’t go on but it doesn’t require any attention during its lifetime.
Tires do require attention most importantly in the matter of pressure. For reasons that baffle (and sometimes infuriate) tire people it is established in many people’s minds that the recommended inflation pressure by either the car or tire manufacturer is some sort of a sneaky dodge to get people to wear out their tires more quickly than necessary.
They cannily set the pressure two or three or five pounds lighter or heavier to prove they can’t be taken in and then forget about tire pressure completely until the tire needs replacement.
A tire pumped to a higher than necessary pressure will grow more rigid and the center of the tread which is supposed to be flat against the road will take on a rounded shape. That rounded shape will wear out quicker of course than the edges of the tire which don’t touch the ground.
A tire not pumped up enough will produce the opposite reaction; it will wear out its outer edges first. Either way if it’s not pumped up the way it’s supposed to be it will not only give much less service but more important will often make driving actually hazardous?
Tire men on the slightest provocation will suddenly deliver long and impassioned speeches about people’s attitude toward tires. If a man is willing to pay at least $100 and most often much more than that for good tires to put on his car why won’t he invest a dollar in a tire pressure gauge and use it say once a month when he knows that improperly inflated tires are not only going to wear out quickly but could likely kill him in the process?
Until people get in the habit of doing that (and just looking once in a while at their tires for signs of uneven wear caused by out of alignment wheels and other causes) all the genius and effort of tire engineers isn’t going to be good enough to finally realize Harvey Firestone’s ambition to put a set of tires on a car that will outlast the vehicle.