It’s something we see every day and take for granted, but in reality, the car wheel is a result of several decades’ worth of engineering and redesign.
The basics design of the wheel hasn’t altered much since the beginning—central hub with spokes or rods radiating out to a circular tire support surface. The reason hubs have spokes is simply to save weight and keep the vehicle as light as possible. The heavier the wheel, the more uncomfortable the travel, especially when the car has to break.
The basic parts of a wheel are…the Hub (or center disc), Lug, Spoke, Rim (or outer lip), Barrel, Tire, and Valve Stem.
In the very center of the hub may be a center bore or a center cap but either will be surrounded by lug holes for bolts to fit through. Of course, securing the wheel to your vehicle are lug nuts. Exactly why lug nuts are called lug nuts is a bit of a mystery. Handles are sometimes known as lugs, but these aren’t exactly handled? If you have any information about this let us know.
Around the edge of the wheel is the tire. It seems that tires go back to the very first gas-powered car in 1888. Before then tires used for carts and steam engines were metallic, and amazingly most people felt that pneumatic tires were as revolutionary as the horseless carriage itself. As with the spokes it is all about keeping the weight down as much as possible.
Strangely, given the usefulness of the pneumatic tires, they didn’t catch on for another seven years. Finally, a car featured in the automobile race from Paris to Bordeaux used pneumatic tires. These cities are only about 400 miles apart but at the time cars routinely broke down, making this race an “endurance race.” The pneumatic tires performed well, keeping the car moving, and garnered the attention they deserved.
Although we now associate tires with having a tread or a specific pattern the idea of incorporating this into a tire’s design didn’t start until 1920. Nowadays it is possible to know who made a tire simply from the tread alone.
While tires quickly took on the look we’re accustomed to seeing they didn’t start making them from synthetic rubber until about 1931. At that time Du Pont industrialized the manufacturer of the rubber, similar to the way that Henry Ford had industrialized the manufacturer the main chassis of the car a few decades earlier. Everything was moving to make the whole process of creating a car more efficient.
Miraculous and ubiquitous as the car modern rubber car tire is, their Achilles heel is obvious–when they become flat they no longer function. To combat this problem, Michelin first invented a “semi-bullet-proof” tire in 1935, which was ultimately too expensive for all but military and bank armored cars. Then in 1958 Chrysler and Goodyear teamed up to create an interlining that prevented blow-outs. In 1972 Dunlop launched their version with the Total Mobility Tyre which became their TD/Denloc tire. Eventually, the Modern run-flat tires were born.
The strategy of most of these tires is to either an inner lining that is “self-sealing” or to insert an inner ring capable of carrying the car’s weight. The latter solution is more rugged and preferred for “armored” vehicles, where weight is an issue.
The only real solution when encountering a flat is to change the wheel. For decades the answer was to carry a “spare,” but in more recent times the practice of carrying an entire replacement tire has morphed into small “donut” tire suitable for only a short distance. This saves valuable weight (and therefore fuel cost) and takes up less room in the trunk. Most recently new cars are selling without a spare of any kind because people hate changing their own tires and prefer roadside assistance.
Not only are car wheels important for getting your around, but they are also intimately involved with the braking system, but that’s a story for another day. Just know that properly working wheels may save your life.