Rabu, 04 Mei 2011

Free Articles

Free Articles

An Helmet

Do not forget to bring your helmet with you!

A helmet is a form of protective gear worn on the head to protect it from injuries.
Ceremonial or symbolic helmets (e.g., English policeman's helmet) without protective function are sometimes used. The oldest known use of helmets was by Assyrian soldiers in 900BC, who wore thick leather or bronze helmets to protect the head from blunt object and sword blows and arrow strikes in combat. Soldiers still wear helmets, now often made from lightweight plastic materials.

In civilian life, helmets are used for recreational activities and sports (e.g., jockeys in horse racing, American football, ice hockey, cricket, and rock climbing); dangerous work activities (e.g., construction, mining, riot police); and transportation (e.g., Motorcycle helmets and bicycle helmets). Since the 1990s, most helmets are made from resin or plastic, which may be reinforced with fibers such as aramids.

All helmets attempt to protect the user's head by absorbing mechanical energy and protecting against penetration. Their structure and protective capacity are altered in high-energy impacts. Beside their energy-absorption capability, their volume and weight are also important issues, since higher volume and weight increase the injury risk for the user's head and neck. Anatomical helmets adapted to the inner head structure were invented by neurosurgeons at the end of the 20th century.


Minggu, 21 Februari 2010

A Spider-man Helmet for kids

Saturday, I went with my beloved wife, Susana. We got our breakfast, and met this boy, with his SPIDER-MAN helmet. I asked his father to take his pictures (and video too).

Rabu, 28 Oktober 2009

A Spider-man Helmet

A helmet with SPIDER-MAN pictures.

A Batman Helmet

A boy with his 'BATMAN' helmet.

Senin, 21 September 2009

A SUPERMAN seat cover for motorcyle

A seat cover for motorcyle with SUPERMAN pictures!

Jumat, 07 November 2008

A Beginners Guide To Motorcyles by steven cask

A motorcycle is a single-track motor vehicle with two wheels, an internal combustion engine, and at least one cylinder. There are bikes to fit many lifestyles, including touring bikes for long road trips, "crotch rockets" for speed, and bikes for city traffic, cruising, etc. Motorbikes are inexpensive and readily available in many countries, making them a popular form of transportation.

Two German inventors, namely Wilhelm MayBach and Gottlieb Daimler were the first to design and build a motorbike in the year 1885 in Bad Cannstatt. However, if we consider a steam operated, two wheel motorbike, then the first such motorbike could be an American one that was built by Roxbury, Massachusetts-based Sylvester Howard Roper in 1867.

Hillenbrand & Wolf Muller became the first motorcycle available for purchase, in 1894. Then as the engines became more powerful and the designs outgrew the bicycle origins, the number of motorbike producers increased. Till the First World War, the largest motorcycle manufacturer in the world was Indian. By 1920, this honor went to Harley-Davidson and in 1928 DKW took over. After the Second World War, BSA Group became the largest producer. And from 1955 until the 1970s the German company NSU Motorenwerke AG held the position .Today, the Japanese manufacturers, Honda, Kawasaki, Suzuki, and Yamaha dominate.

To get a motorbike construction as desired by the designer, the engineering, manufacturing, and assembly of components and systems must be taken into account. The construction of contemporary mass-produced motorcycles uses a mostly standardized steel or aluminum frame, disc brakes, and telescopic forks to hold the front wheel. They usually have a one- to six-cylinder gasoline-powered engine.

Those motorbikes that have a short wheelbase, such as sport bikes, have the ability to generate enough torque at the drive wheel, and with enough stopping power at the front wheel will be able to lift the other wheel off the ground. This is commonly known as doing a wheelie and a stoppie respectively. If the driver gets too carried away to past the point of no return, it will cause an upset which is known as "looping" the vehicle.

We must also be aware that the motorbike fuel economy benefits from a relatively small mass of the vehicle, compared to the passengers and to the other motor vehicles, and the subsequent small engine displacement. Riding style has a large effect on fuel economy: some riders report being able to double fuel economy by using low accelerations and lower speeds than usual, although this is the extreme case.

About the Author

As an avid motorcyclist for over 35 years riding all different types of motorcycles, dirt bikes, sport bikes, cruisers and touring bikes. My many miles of riding in all kinds of weather and conditions gives me extensive expertise in the field of motorcycles , motorcycle motorcycle clothing and accessories.

taken from : http://www.goarticles.com/cgi-bin/showa.cgi?C=738906