08/30/2011

• Cadel Evans wins the Tour de France on tyres from Continental
• The corporation has been developing and producing bicycle tyres since 1892
• The pneumatic tyre was invented twice, both in England and in Ireland

Hanover, August 2011. An entire continent is celebrating: The Australian Cadel Evans wins the Tour de France, making him the first ever Australian winner of the "Le Tour" challenge. After around 3,600 kilometres, he beat the brothers Andy and Frank Schleck from Luxembourg to the finishing line. The BMC Racing Team cyclist did not only have greater staying power during the decisive stages, but was also one step ahead during the individual time trials. This victory was only possible due to perfect cooperation and interplay between suppliers, the athlete, the team and technicians.

The winning team put its trust in Continental’s expertise and tyres. The special hand-made tyres from Korbach in Hesse only weigh 250 grams, and as opposed to other bicycle tyres, are made out of a coated tube whose outer surface has a fine ribbed profile and which withstands internal pressures of up to 12 bar. The most striking feature is the rolling resistance-optimized, extremely narrow contact surface, which is able to safely transfer steering commands and braking forces to the road when cycling downhill at speeds of 100 km/h. "The choice of tyre in the Tour de France is a gamble and is now as important as the choice of tyre in Formula 1," says Constantin Batsch, manager of the Continental two-wheel tyres business unit. A host of engineers are involved in materials research for bicycles and accessories. It is no coincidence that the average 25 kilometres per hour achieved in the world’s first stage road race in 1903, has meanwhile increased to almost 40, and that when the route profile has been getting increasingly difficult.

Incidentally, the forerunner of the bicycle was invented in 1817 by the German inventor Karl von Drais. His vehicle rolled on metal-shod wooden wheels. It was only from 1865 onward that the vehicle was driven by a pedal crank attached to the front wheel. Two years on, cycling made its debut as a sport in Paris. The route ran approximately 23 kilometres from the Champs-Élysées to the Palace of Versailles. Technology rapidly developed from this time on. When the Englishman James Moore won the world’s first long-distance race in 1869 – over 122 km from Paris to Rouen, his Suriray velocipede was already equipped with ball bearings, solid rubber tyres on metal rims and freewheel. It was to be another 20 years before the air-filled tyre became a success. The first bike race with air-filled tyres took place in 1889 in Belfast. The bike we know and use today existed even then, shortly after the introduction of the diamond frame. All further developments and inventions only relate to components or are reinventions of constructions which already existed.

Pneumatic tyres, for example, were invented twice. The English railroad engineer William Thomson pursued revolutionary development goals when he invented and patented the first rubber pneumatic tyre in 1845: low rolling resistance, vibration damping and noise reduction. Already in 1847, he conducted experiments using a pneumatic tyre where the cover was made out of vulcanized natural rubber. The invention, however, was forgotten by the time he had died in 1873. Nearly everything on the roads rolled on metal-shod or wooden wheels. Roads were poor and strewn with sharp stones and nails which had come loose from the wooden wheels and rims. Because of these road conditions the sensitive pneumatic tyres didn’t initially stand a chance.

Road conditions had changed by 1888 when the Irish veterinary surgeon John Dunlop came up with the same idea and stretched rubber-coated linen over an air-filled rubber tube which he then mounted on a wooden wheel, later to be replaced by a spoke rim. Bicycles were equipped with pedals and were very popular. Carl Benz and Gottlieb Daimler had just tested their automobile. Initial difficulties still, however, had to be overcome. Dunlop’s pneumatic tyres were fixed to the wheel. After getting a flat tyre (which happened quite frequently), the rubber layers had to be laboriously removed with benzine and unwound to reveal the tube. The first well base rim initially remedied this. A short time later, William Bartlett first used air pressure to push the thicker end of the tyre (bead) into a bent-over rim. From this time on, anyone could buy individual tyres, replacement tyres in particular, and easily fit them themselves. In 1891 Charles Woods invented a valve, the principle of which is still used today.

Continental began development and series production of bicycle tyres in the following year. Following several design related improvements, which for the most part were to stabilize the tyre, tyres were first equipped with treads in 1904, back then the treads ran longitudinally to the tyre. This was because for the speeds achieved at the time, the problem was not the tyre slipping on the contact surface but rather it slipping laterally. It was only five years later that the Hanover-based company started automobile tyre production.

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