The next time that you are powering your car into a corner, just spare a thought for the few square inches of rubber that are keeping you from sliding into the ditch. While we put plenty of faith in our tyres we rarely stop to consider quite how extraordinary our tyres are. But it hasn’t always been the case, and the evolution of the tyre is a tale of high-technology that often goes unappreciated.
The need for Rubber
Prior to 1888 any road-going vehicle was shod in solid rubber bands that helped iron out the lumps and bumps in the road. Poor on shock absorption and badly made, solid tyres came to the end of their useful life with the advent of the Benz gasoline-powered car and a notable increase in speed it provided.
But we need to look back a bit further to 1839 when Charles Goodyear found that by adding Sulphur to latex, the new materials showed the desired properties that a road-going vehicle needed. Rubber tyres – despite the fact that they were solid – were both hardwearing and supportive. Termed ‘vulcanized rubber’ this was a credible material that could be used for continuous running on hard surfaces, and became the first important step in road wheel comfort and control.
Putting Air in it
The second major breakthrough came with the invention and development of the pneumatic tyre. While usually credited to John Boyd Dunlop in 1888, it was actually the work of another Scotsman – Robert William Thompson – who had patented the idea of an air-filled tyre back in 1845, but Dunlop improved on it and after a prolonged legal battle, it was Dunlop’s idea that became the accepted design. Dunlop’s patent incorporated a sealed, inflated rubber tube that sat in a shaped form on the outside of the wheel, and was the first to use the word ‘pneumatic’ in its description, to differentiate it from Thompson’s earlier patent. The same decade also saw the development of the air valve and proper detachable tyres.
The pneumatic tyre showed its worth when it was entered in a series of bicycle races at Queen’s College sports in Belfast and other events in Liverpool. Following this, Harvey Du Cros, one of the losers in those races, recognized the worth of the tyre and formed a company with Dunlop to exploit the product. Commercial tyre production for bicycles began in 1890, but the pneumatic car tyre wasn’t fully developed for another ten years and Dunlop never really made any great fortune from his invention. Pneumatic tyres soon gave way to inflated tubes within tyres, and steel braiding around the periphery allowed the tyres to remain on wheel hubs under huge loads.
Keeping Cars on the Road
Plainly, car development was becoming the major driving force for technology, and that included the tyre too. As the internal combustion engine became understood and improved upon, car manufacturers started to toy with engine size and power, and that meant asking a lot more of tyres. In 1903, C H Gray and T Sloper filed a patent which fitted cords in the rubber to increase stiffness and durability on the road surface and quickly became the standard design for tyre construction. Tyres were now constructed of a durable material, they had inner tubes with valves that allowed both inflation and deflation, and were designed to fit tightly onto steel wheels.
With the basics of tyre design in place, manufacturers began to experiment with the form of tyre construction and significant effort was applied to tread patterns and how the tyre actually addressed the road. Tread patterns are a hugely important part of tyre design. Tread patterns had first appeared in the 1890’s on bicycle tyres but it wasn’t until 1908 that they first appeared as ‘stability slots’ on Firestone tyres and, while racing slicks were seen as the best for grip on dry surfaces, roads, treaded tyres were the best for all round conditions. Thus began a huge drive to develop the best tread patterns for all weathers and surfaces.
The next major development in tyre design was the introduction of radial construction. Ever since cords has been incorporated into the vulcanized rubber for stability and strength, designs had been of the Crossply types. The corded material went across the section of the tyre like a bandage supporting the flexible rubber. However, in 1946, Michelin introduced the radial tyre which saw the corded material and steel belts extend around the periphery of the tyre. This configuration saw the tyres increase in impact strength while allowing controlled flexibility in the sidewalls. Radial tyres have slowly become the wheel of choice and while Crossply tyres are still available, they tend to be reserved for classic and vintage cars.
Whether for bicycles, cars, trucks or racing cars, tyres have undergone a huge amount of development to make them safer, easier to use, and offering greater comfort. They are so important that there are tyre laws in every country to ensure that tyres are fit for use on roads and there are big fines to be had if yours are not. Go and check them now!
Author Bio: Giles Kirkland is a car tyres expert at Oponeo, as well as a motorization fan and a committed writer. He especially enjoys reading and writing about vintage cars.