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Harley Davidson Evolution

The history of the Harley-Davidson motorcycle began in Milwaukee in 1903. In Milwaukee, Bill Harley and Arthur Walter Davidson developed a one-cylinder motorcycle. Around the turn of the century the gasoline engine was developed and the one-cylinder motor was introduced. The bike was built to be a racer, with a 3-1/8 inch bore and 3-1/2 inch stroke. The factory in which they worked was a 10 x 15-foot wooden shed with the words "Harley-Davidson Motor Company" crudely scrawled on the door. Arthur's brother Walter later joins their efforts. Work immediately began on a new and improved second-generation machine. This first "real" Harley-Davidson motorcycle had a bigger engine of 24.74 cubic inches (405 cc) with 9.75 inches (25 cm) flywheels weighing 28 lb (13 kg). The machine's advanced loop-frame pattern was similar to the 1903 Milwaukee Merkel motorcycle . The bigger engine and loop-frame design took it out of the motorized-bicycle category and would help define what a modern motorcycle should contain in the years to come. The boys also received help with their bigger engine from outboard motor pioneer Ole Evinrude who was then building gas engines of his own design for automotive use on Milwaukee's Lake Street.

Motorcycle begins

Motorcycle history begins in the second half of the 19th century. Motorcycles are descended from the "safety bicycle," a bicycle with front and rear wheels of the same size and a pedal crank mechanism to drive the rear wheel. Those bicycles, in turn were descended from high-wheel bicycles. The high-wheelers were descended from an early type of push-bike, without pedals, propelled by the rider's feet pushing against the ground. These appeared around 1800, used iron-banded wagon wheels, and were called "bone-crushers," both for their jarring ride, and their tendency to toss their riders.

Despite some early landmarks

in its development, motorcycles lack a rigid pedigree that can be traced back to a single idea or machine. Instead, the idea seems to have occurred to numerous engineers and inv

entors around Europe more-or-less simultaneously

The first motorcycle was built in 1885 by Gottlieb Daimler, an engineer, industrial designer and industrialist, born in Schorndorf (Kingdom of Wurttemberg, a federal state of the German Confederation), in what is now the Federal Republic of Germany.

The motorcycle had one wheel in the front and one in the back, although it had a smaller

spring-loaded outrigger wheel on each side. It

was constructed mostly of wood, with the wheels being of the iron-banded wooden-spoked wagon-type, definitely a "bone-crusher" chassis. It was indeed powered by a single-cylinder Otto-cycle engine, and may have had a spray-type carburetor. (Daimler's assistant, Wilhelm Maybach was working on the invention of the spray carburetor at the time).

If one counts two wheels with steam propulsion as being a motorcycle, then the first one may have been American. One such machine was demonstrated at fairs and circuses in the eastern US in 1867, built by one Sylvester Howard Roper of Roxbury, Massachusetts. There is an existing example of a Roper machine, dated 1869. It's powered by a charcoal-fired two-cylinder engine, whose connecting rods directly drive a crank on the rear wheel. This machine predates the invention of the safety bicycle by many years, so its chassis is also based on the "boneshaker" bike.

In 1868, the French engineer Louis-Guillaume Perreaux patented a similar steam-powered vehicle, which was probably invented independent of Roper's. In this case, although a patent exists that is dated 1868, nothing indicates the invention had been operable before 1871.

Nevertheless, these steam-powered vehicles were invented prior to the first petroleum-powered motorcycle.

In the decade from the late 1880s, dozens of designs and machines emerged, particularly in France, Germany and England, and soon spread to America. During this early period of motorcycle history, there were many manufacturers since bicycle makers were adapting their designs for the new internal combustion engine

The first really successful production two-wheeler though, was the Hildebrand & Wolfmueller, patented in Munich in 1894. It had a step-through frame, with its fuel tank mounted on the downtube. The engine was a parallel-twin, mounted low on the frame, with its cylinders going fore-and-aft. The connecting rods connected directly to a crank on the rear axle, and instead of using heavy flywheels for energy storage between cylinder-firing, it used a pair of stout elastic bands, one on each side outboard of the cylinders, to help out on the compression strokes. It was water-cooled, and had a water tank/radiator built into the top of the rear fender.

Hildebrand & Wolfmueller became the first motorcycle available to the public for purchase. However, only a few hundred examples of this motorcycle were ever built. Soon, as the engines became more powerful and designs outgrew the bicycle origins, the number of motorcycle-oriented producers increased.

In 1895, the French firm of DeDion-Buton built an engine that was to make the mass production and common use of motorcycles possible. It was a small, light, high revving four-stroke single, and used battery-and-coil ignition, doing away with the troublesome hot-tube. Bore and stroke figures of 50mm by 70mm gave a displacement of 138cc. A total loss lubrication system was employed to drip oil into the crankcase through a metering valve, which then sloshed around to lubricate and cool components before dumping it on the ground via a breather. DeDion-Buton used this 1/2 horsepower powerplant in roadgoing trikes, but the engine was copied and used by everybody, including Indian and Harley-Davidson in the U.S.