Frames and Materials
The pneumatic tire and the chain drive, followed by the development of gears, revolutionized bicycling in the later 1800s. In the last fifteen years, there has been a revolution of sorts in the development and use of new materials for building frames. It wasn't that long ago that frames were made out of cast iron or even wood. Today bicycles are made out of exotic materials such as titanium, aluminum, and carbon fiber. Bicycle frames in the 1990s are lighter and stronger than ever before.
German Inventor Karl von Drais is credited with developing the first bicycle. His machine, known as the "swiftwalker," hit the road in 1817. This early bicycle had no pedals, and its frame was a wooden beam. The device had two wooden wheels with iron rims and leather-covered tires. As the name suggests, a rider walked on top of the bike with his feet leaving the ground during descents.
Age of the Velocipedes
While it might seem simple and obvious now, getting the rider's feet completely off the ground was a major step (excuse the pun) forward in the development of the bicycle. The rider used pedal-cranks attached to the hub of a wheel to propel himself. There is a dispute as to who invented the machine that became known as the "velocipede," but there is no question as to its impact.
The velocipedes of the mid 1800s consisted of two wooden tires, a front fork, handlebars for steering, a saddle on wooden frame, and pedals on the axle of the front wheel. The velocipede also received a nickname, the "boneshaker." With the rider now completely mounted on the bicycle, he felt all of the bumps--the early velocipedes were not equipped for absorbing vibrations. It wasn't until the development of the pneumatic tire that this problem was effectively addressed. At around the same time the pneumatic tire was developed (1888), lighter materials began to be used for frames, improving the ride dramatically.
Materials for Frames
By the time the modern "safety" bicycle was developed in the late 1800s most frames were made with steel tubing instead of wood or cast iron. While the steel bicycles were quite strong they were also very heavy. It was not uncommon for a bicycle of that era to weigh in at over 80 pounds (36.28 kg.).
Steel frames are still used today, but the tubing has thinner walls and weighs considerably less. Modern frame makers such as Paolo Salvagione use a variety of materials for highly specialized bikes. Paolo uses steel, aluminum, titanium, and even carbon-fiber. Which material he uses depends on the type of bike, the rider's preference, and the cost. We asked Paolo to tell us about the unique qualities of each material.