Since 2004, the rim has been defined as “the tire and tube assembly or support for the tubeless tire on which the bead of the tire rests”.
In the early years of the automobile, the tire was glued to the wooden wheel, and it was long and arduous to repair. We had to wait for the Michelin brothers’ invention of the removable tire to discover the benefits of the steel rim; A steel plate that became common in the 1920s.
heat is a problem
When manufacturers adopted rims made of sheet steel, the first concern came from the evacuation of heat from the brakes, hidden behind a metal curtain.
When these drum brakes got hot, they lost their effectiveness in braking the vehicle. We then started drilling holes in the rims to improve cooling.
But the weight was still significant, which negatively affected the ride due to its inertia. For the competition, we found spoked wheels that make cooling easier.
The answer is in aluminum alloy
It took the genius of Ettore Bugatti to tackle these problems. You have to go back a little in time. In 1886, inventor Charles Martin Hall and chemist Paul Héroult independently developed an electrolytic process for the removal of aluminum.
In 1920, race car manufacturer Harry A. Miller came up with the idea of making aluminum wheels. He applied for a patent, but ultimately did not produce wheels.
alloy wheels for Bugatti 35
The founder of the famous brand, Ettore Bugatti, succeeded in casting aluminum wheels and brake drums in one of his foundries, using the molds he produced, or even produced, in a very short time.
Always a perfectionist, Bugatti has applied for more than 500 patents with new ideas for its wheels.
In 1924, the Bugatti 35 replaced its spoked wheels with eight-spoke aluminum alloy wheels.
The first race in September 1924 was a disaster; all the cars gave up. Due to poor quality tires. Cast aluminum will continue on its way.
Back then, the wheels made up about a quarter of a vehicle’s aerodynamic drag. Ettore Bugatti believes that better distributed airflow with well-designed wheels will lead to better heat dissipation.
In competition, being able to quickly dissipate the heat generated during braking is essential. Good cooling is a guarantee of more effective braking. The purpose of Bugatti’s flat rails was to disperse the hot air without accumulating heat.
Forged or cast rim
Today, there are two types of alloy wheels: cast (for standard or economy production) or forged and then machined for best-in-class models. A technique that allows for a wide variety of designs.
Among the advantages is that they are lighter than sheet steel wheels, which gives the car a better liveliness.
On the other hand, they can be easily scratched and lose their shiny appearance. Finally, it is not recommended to install snow tires on alloy wheels; their reduced weight does not allow the snow tire to grip on slippery ground as if mounted on a steel rim.