MOTORCYCLE is a two- or three-wheeled vehicle powered by a gasoline engine mounted midway between the front and rear wheels. A motorcycle has a much heavier and stronger frame than a bicycle, the vehicle from which it was developed. People in many parts of the world use motorcycles for transportation or ride them for recreation and sport. Many police departments use motorcycles for pursuit and traffic control because these vehicles can be maneuvered easily through traffic. Some fire departments use motorcycles to transport medical personnel to accident scenes. Many motorcyclists call their machines "bikes."
In the United States and Canada, motor vehicle laws affect the operation of
motorcycles as well as of automobiles and other kinds of vehicles. In a few
states and provinces, a motorcyclist needs only a regular driver's license.
However, nearly all the states and provinces require cyclists to have a
motorcycle operator's license, for which a person must pass a test. One test
used by many licensing agencies is the Motorcycle Operator Skills Test (MOST).
In order to pass this test, cyclists must be able to demonstrate skill in
handling a motorcycle. Many states and provinces also require cyclists to wear
safety helmets and protection for their eyes.
Motorcycling is popular throughout the world. In regions where gasoline is
usually more expensive, such as East Asia, Europe, and South America,
motorcycles are regarded as convenient and inexpensive transportation. In the
United States and Canada, motorcycles are widely used for recreation, as well as
for transportation to jobs. In urban areas, motorcycles help to reduce traffic
congestion and air pollution.
Kinds of Motorcycles. Manufacturers produce motorcycles in a variety of sizes, types, and weights. The two main kinds are (1) those designed primarily for use on streets and other paved surfaces, and (2) those intended chiefly for off-road riding. The first group consists of street and touring bikes and motor scooters. The second group includes trail bikes and a variety of other related off-road vehicles.
Street Bikes are used on roads and highways for short or long trips and for in-town riding. They weigh from 235 to 500 pounds (110 to 230 kilograms) and can travel at all legal highway speeds.
Touring Bikes are street bikes that carry special equipment for long-distance travel. For example, many touring bikes are equipped with windshields to provide extra protection against the wind, and compartments to carry luggage. Touring bikes weigh from 500 to 900 pounds (230 to 410 kilograms) and can usually travel at greater speeds than street bikes can.
Trail Bikes can travel on rough country trails, climb hills, and cross streams. They have deeply grooved tires that provide traction on gravel and other rough surfaces. They weigh from 150 to 250 pounds (68 to 110 kilograms).
Motor Scooters are not technically motorcycles, because their engine is mounted over or directly in front of the rear wheel. They are also more compact than motorcycles and designed for use at lower speeds. In addition, the driver of a motor scooter sits with both feet on a floorboard.
Minibikes and Minicycles have motorcycle-type engines but weigh less and are more compact than most motorcycles. They are not built for use on paved roads.
Motorbikes include mopeds (pronounced MOH pehdz), which are started by pedaling. Mopeds have an automatic transmission, and can reach a speed of 30 miles (48 kilometers) per hour.
The Parts of a Motorcycle. A motorcycle has five major parts: (1) the engine, (2) the transmission system, (3) the wheels, (4) the brakes, and (5) the controls. A frame of steel or chrome tubing holds them together.
The Engine of a motorcycle has one to six cylinders. It operates on either a two-stroke or four-stroke cycle (see GASOLINE ENGINE [Cycle]).
The Transmission System of most motorcycles consists of four, five, or six gears. Racing models may have as many as eight speeds, and some small models have as few as two.
The Wheels. Most street motorcycles have steel- or aluminum-rimmed wheels with tubeless tires similar to those on automobiles. However, many off-road bikes have rubber tubes inside the tire to hold compressed air. Motorcycle tires have a rounded tread pattern that provides the traction needed for leaning through turns. The front forks, an extension of the frame, help hold the front wheel in place. They serve as a suspension system that cushions the rider against bumps. A rear swing arm allows the rear wheel to move up and down, providing additional stability when riding over bumps.
The Brakes. A motorcycle has front- and rear-wheel brakes, which work separately. The front brake supplies most of the stopping force.
The Controls. The rider uses various hand and foot controls to operate the motorcycle. Most older bikes have a kick starter, but a large number of recent models are equipped with an electric starter instead. A hand twist grip controls the throttle, which regulates the speed of the engine. A hand lever on the left handlebar operates the clutch. A hand lever on the right handlebar controls the front brake, and a foot pedal controls the rear brake. Most motorcycles have a second foot control for shifting gears.
Motorcycle Safety. The Motorcycle Safety Foundation in the United States and the Canada Safety Council in Canada have developed courses to promote motorcycle safety. These classes, which are offered by many community colleges, high schools, and police departments, are designed to develop good riding habits. They also stress the importance of proper cycling clothes, such as a helmet, goggles, gloves, and boots.
Motorcycling as a Sport enables cyclists to compete in such events as dirt-track races, enduros (endurance races), and cross-country races. Dirt-track racing is the most popular type of motorcycle competition. It includes races run on flat, oval tracks and motocrosses, which are run on rugged courses that have jumps, hills, and other obstacles.
Most motorcycle competition is governed by the American Motorcyclist Association (AMA), which has headquarters in Westerville, Ohio. The AMA sponsors a number of annual races. A point system established by the AMA determines a racing champion each year. Cyclists receive points for winning official races or for placing high in the events. The racer who earns the most points becomes Grand National Champion.
History. The first gasoline-powered motorcycle was invented in 1885 by Gottlieb Daimler, a German engineer. He attached a four-stroke piston engine to a wooden bicycle frame. For the next few years, motorcycles remained largely experimental. During the early 1900's, they developed into useful vehicles. Today's motorcycles have the same general appearance as earlier models. But modern bikes are easier to handle, and they have stronger frames, more powerful engines, and more efficient brakes.
Contributor: Gregory B. Harrison ---- end of article ----
