Bicycle
A bicycle, or bike, is a small, human powered land vehicle with a seat, two wheels, two pedals, and a metal chain connected to cogs on the pedals and rear wheel. A frame gives the bike strength, and all of the parts other than the frame are attached to the frame. The name comes from these two wheels - the prefix "bi-" meaning two, and the suffix "-cycle" meaning wheel. It is powered by a person riding on top, who pushes the pedals around with his or her feet.
Riding bicycles, which is also called cycling, is an important way to travel in several parts of the world. It is also a common recreation, a good form of low-impact exercise, and a popular sport. It is also the second most popular spectator sport in the world. Bicycling uses less energy per mile than any other human transport.[1]
Contents |
[change] Invention
In 1817 a German professor, baron Karl von Drais, created the first two wheeled bicycle. It was made of wood and had two wheels. The front wheel could be turned using the handlebars in order to steer the bike. However, it did not have pedals, so the rider would have to push their feet on the ground to make it move.
In the 1860s, French inventors added pedals to the front wheel. However, it took a lot of effort to turn the pedals. Later inventors made the bikes out of metal only and made the front wheel very big, making it easier to pedal. This design was called the penny-farthing bicycle. However, it was difficult to ride, since it could fall over easily.
In 1885, the safety bicycle was invented. This had two wheels the same size so that the rider could sit at a lower height. It was called the safety bicycle because it much easier to ride than the penny-farthing. Instead of pedaling and steering with the front wheel, the safety bicycle used steering with the front wheel while the pedals turned the back wheel using a chain.
The bicycle soon became very popular during the 1890s and a number of improvements were made. In 1888, Scottish inventor John Boyd Dunlop invented a type of tire which was filled with air, and this made cycling far more comfortable. Soon, the freewheel was invented. This was a device inside the hub of the back wheel that allowed the wheel to spin even if the rider wasn't pedalling. However, this meant the rider could no longer stop the bike using the pedals. As a result, a type of brake was invented which could stop the bike if the pedals were turned backwards.
Later inventions included brakes which the rider could use by pulling levers on the handlebars, and gears, which made cycling up and down hills much easier.
[change] Basic Design
Basic components common to most bikes include a seat, pedals, gearing, gear shifter, handlebar, wheels, brakes, cables, and frame elements. The cyclist turns the pedals around in circles, which turns the chain which turns the back wheel of the bike. The front wheel
[change] Types of Bicycles
[change] Mountain Bicycle
The mountain bicycle is used for riding on rough roads. They have many speeds (usually more than 20), wide tires, and powerful wheels. The tire tread is specially designed to ride smoothly on hills, grass, and mountains.
[change] Urban Bicycle
The Urban bicycle is used for the convenient ride around the city. It`s comfortable and has a relatively high speed. It has a comfortable seat but is heavy. It usually has fenders to keep water and mud from spraying the rider.
[change] Woman’s Bicycle
The difference between a woman's bicycle and other bicycles is the location of the top tube. When women began to ride bikes, they wore long skirts. The manufacturers of bicycles changed the location of the top tube to make it easier for women to sit down on them while wearing a skirt.
[change] Tandem Bicycle
The tandem is a bicycle for 2 people. It has two pairs of pedals. The cyclists sit one behind another. The first cyclist steers the bicycle. There are bicycles for 3 and more people. There was a bicycle for 40 people.
[change] Electric Bicycle
Electric bicycles have electric motors normally found inside the hub of either the front or rear wheel. You can choose to ride using the motor only, or with pedals only or with both together.
In the U.S. the federal government has set a limit of 750 Watts and a top electric-powered speed of 20MPH to have only the rules that apply to bicycles and no extra restrictions such as operator license, vehicle license, registration or insurance requirements.
[change] Road Bicycle
A road bicycle usually has smaller tires, less than 1" thick, with a frame that is much lighter than a mountain bicycle. Road bikes are a great option for training longer distances and changing out the pedals for clip in shoes are the best way to go. There are variations, as some road bicycles have regular tires. A road bike can go very fast and is a good choice when participating in a bike race.
[change] Safety
When riding on streets, it is safest to ride on the same side of the street that cars drive (which would mean riding on the right side of the road in countries where people drive on the right side of the road, and riding on the left in countries where people drive on the left).. To avoid hitting people, riders must obey signs that say "no bicycling", even if it does not seem to make sense at the time. Low light makes bicycle lighting important; so without bicycle lighting, it may be safer not to ride. Wearing a helmet makes bicycle riding safer. More than 300,000 people children alone to go to a hospital every year because they were hurt riding a bicycle.[2] Wearing a helmet does not mean that somebody cannot be hurt if they crash their bicycle, but it makes being hurt less likely.[3] Some bicycles have bells or horns that the rider can use to warn other people that they are riding by them.
[change] References
- ↑ "Science of Cycling: Human Power". www.exploratorium.edu. pp. 1. http://www.exploratorium.edu/cycling/humanpower1.html. Retrieved 2007-08-11.
- ↑ "Bike Safety". kidshealth.org. http://kidshealth.org/kid/watch/out/bike_safety.html. Retrieved July 29, 2010.
- ↑ "Helmets: How they Work and What Standards Do". bhsi.org. http://www.bhsi.org/general.htm. Retrieved July 29, 2010.
[change] Other pages
