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Harley-Davidson is an American manufacturer of motorcycles. Harley-Davidson motorcycles are distinctive in design and attract a loyal following. Bikers who are not fans contend that the bikes are badly engineered, under-powered and under-performing, and have poor handling, mainly as a result of their American pedigree (designed for long, low-speed cruising on flat, straight roads.)

The Harley-Davidson Motor Company supplies many police forces with their motorcycle fleets.

Table of contents
1 The Harley-Davidson V-twin engine
2 History
3 The 100th Aniversary
4 External links

The Harley-Davidson V-twin engine

Harley-Davidson 45° V-twin
The classic Harley-Davidson engines are two-cylinder, V-twin engines with the pistons placed at a 45 degree angle. The engine design, which is covered under several United States patents, produces the unique, signature throbbing sound of the Harley-Davidson power plant.

The crankshaft has a single pin, and both pistons are connected to this pin through their connecting rods. This design causes the pistons not to fire at even intervals.

The V-twin runs like this: The first piston fires. Then, the other piston fires at 315 degrees into the stroke. There is a 405-degree gap until ... the first piston fires again. This give the Harley-Davidson V-twin it's unique pop-pop...pop-pop...pop-pop sound.

Harley Davidson Co endeavoured to file as a registered trade mark the distinctive sound of a Harley Davidson motorcycle engine. On 1 February 1994, the company filed an application for a sound trade mark: "The mark consists of the exhaust sound of applicant's motorcycles, produced by V-twin, common crankpin motorcycle engines when the goods are in use". Nine of Harley Davidson's competitors filed oppositions against the application, arguing that cruiser-style motorcycles of various brands use the same crankpin V-twin engine which produces the same sound. After six years of litigation, with no end in sight, in early 2000 Harley Davidson withdrew their application.

Harley-Davidson Electra Glide
“Ultra Classic”

Engine models include:

Recently, Harley-Davidson introduced a completely new 60° V-twin, the "Revolution" engine. This was followed by the water cooled V-Rod engine.


Motorcycle models include the models designated with F (meaning Big Twin), X (meaning Sportster), FL (Big Twin with Hydraglide big forks), and FX (Big Twin with Sportster-style smaller forks).


Founding of the Motor Company

The Harley-Davidson enterprise got off to a less than auspicious start in Milwaukee in 1901 when William Harley, 21 and Arthur Davidson, 20, built a prototype motorized bicycle. It was built in the Davidson garage, which measured only 10 by 15 feet. Once their prototype was functional, they were joined by Davidson's two brothers William and Walter.

Harley-Davidson Trike

In their first two years, they only managed to produce 3 motorcycles.

The Harley-Davidson Motor Company was officially founded on August 28, 1903, and they officially started production. They had made some pretty big changes from the early prototypes, including a redesigned frame. Still, the 1903 production was only 3 bikes.

In 1906 they built their first real building on Juneau Avenue, which is still the location of the company today. They had been ramping production up gradually, and with the new facilities they were able to produce 150 motorcycles in 1907, an important year in the life of the fledgling company. They began selling their motorcycles to police fleets, a tradition that continues today.

The early bikes had a single-piston engine. In 1909 a 45-degree V-Twin engine was introduced. The first V-Twin wasn't the powerhouse that it is today. It displaced only 49.6 cubic inches and produced only seven horsepower. Still, that was double the horses of the first bikes. The top speed was 60 miles per hour, quite a speed in those days. Production was 1,149 motorcycles.

The success of the company had begun to attract attention, and Harley-Davidson had over 150 competitors by 1911.

By 1913 the original factory, which measured only 28 by 80 feet, had been expanded to a roomy 297,110 square feet. Despite the harsh competition, Harley-Davidson was already pulling ahead of the pack, completely dominating motorcycle racing. Production had swelled to 12,904 machines.

World War I Era

In 1917, the United States was drawn into World War I. The military demanded motorcycles for the war effort. Harleys had already been used by the military in border skirmishes with Pancho Villa, but World War I was the first time the motorcycle had been broadly adopted for combat service. The company had consolidated its position as the motorcycle of choice for police forces. Harley-Davidson provided over 20,000 machines to the military forces during World War I.

By 1920, Harley-Davidson was officially the largest motorcycle manufacturer in the world. Their motorcycles were sold by dealers in 67 countries. Production was 28,189 machines.

In 1921, a milestone was reached in motorcycle racing. A Harley-Davidson machine was the very first to win a race at an average speed of over 100 miles per hour.

During the 1920s, several improvements were put in place, such as a new 74 cubic inch V-Twin, introduced in 1922, and the gas tank we still see today, called a "Teardrop" tank, in 1925. A front brake was added in 1928.

World War II Era

One of only two American cycle manufacturers to survive the Great Depression, Harley-Davidson again produced large numbers of motorcycles for the army in World War II and resumed civilian production afterwards, producing a range of large V-twin motorcycles that were successful both on racetracks and for private buyers.

Modern Era

By the 1970s, however, the Harley Davidson Company had ceased to be an innovator in the motorcycle industry, and the design had remained basically unchanged for many years. The bikes were expensive and far inferior in performance, handling, and quality to Japanese motorcycles. AMF bought the company and ramped up production, but this tactic resulted in even worse quality bikes. Sales declined, quality plummeted, and the company almost went out of business. The venerable name of "Harley Davidson" was mocked as "Hardly Able", and the nickname "hog" was both affectionate and perjorative. AMF sold the company back to a small group of investors, who slowed production, introduced innovative production techniques, and improved quality. Rather than trying to match the Japanese at their own game, this new management deliberately exploited the "retro" appeal of the machines, building motorcycles that deliberately aped the look and feel of their earlier machines and the subsequent customizations of owners of that era. Quality was better, and technical improvements have been made, but these goals were never achieved at the cost of substantially modifying the design of the machine except by gradual degrees.

Even a brand new Harley therefore is in some respects a classic waiting to happen. Probably for this reason, as well as their general collectibility, Harley-Davidson motorcycles hold their resale value very well compared to other vehicles. A well maintained vehicle might never drop in value at all, although regular maintenance and customization are expected.

Similarly, the company now makes more money selling licensed merchandise featuring the Harley-Davidson logo than selling motorcyles.

Today, Harley-Davidson is considered an example of an American company that turned itself around from the brink of bankruptcy and back to profitability.

The 100th Aniversary

In 2003, Harley-Davidson celebrated it's 100th birthday. On labor day weekend the City of Milwaukee (the home of HD) hosted the biggest Harley-Davidson event, if not the largest motorcycle event, in history.

External links