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Bicycle

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Early bicycles
A modern mountain bike; its thick, wide tires allow it to be used on rocky trails

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

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[change] Invention

Wooden Draisine (around 1820), the first two-wheeler

In 1817 a German professor, baron Karl von Drais, created the first two wheeled bicycle. It had a handlebar, and looked like a bicycle of today, but it didn`t have pedals, and it had a wooden body.

[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

It is very important to ride on the safe side of the road for the direction of motion. To avoiding hitting people, obey signs that say "no bicycling", even if it does not seem to make sense at the time. Low light makes bicycle lighting important; therefore, without bicycle lighting, it may be safer not to ride. It is also very important to correctly wear a helmet, because falling down from the bicycle many times in a lifetime of bicycle riding is very likely.[needs proving] Bells that a bicycle user can put on the handlebars and ring while riding also exist.

[change] References

  1. ↑ Science of Cycling: Human Power 1. www.exploratorium.edu. Retrieved on 11 August 2007.

[change] Other pages

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