Selasa, 23 Oktober 2007

Sejarah Harley Davidson










HARLEY DAVIDSON
Harley-DavidsonHarley-Davidson Motor Company (NYSE: HOG) is an American manufacturer of motorcycles based in Milwaukee, Wisconsin, United States. The company emphasizes heavyweight (over 750 cc) bikes designed for cruising on the highway and known for their distinctive exhaust note.Harley-Davidson motorcycles (popularly known as "Harleys") are distinctive in design and sound, attracting a loyal following (in marketing terms, the owners form a brand community). The Motor Company supplies many American police forces with their motorcycle fleets. Harleys are especially noted for the tradition of heavy customization that gave rise to the chopper-style of motorcycle. It also licenses its logo, which is a profitable side business ($ 41 million of revenue in 2004, or almost 5 % of net income).Since 1998 the Buell Motorcycle Company is a 98 % subsidiary of Harley-Davidson.



The Harley-Davidson engines
The classic Harley-Davidson engines are two-cylinder, V-twin engines with the pistons mounted in a 45° "V". The crankshaft has a single pin, and both pistons are connected to this pin through their connecting rods.This design causes the pistons to fire at uneven intervals, the consequence of an engineering tradeoff to create a large, powerful engine in a small space. This design choice is entirely vestigial from an engineering standpoint, but has been sustained because of the strong connection between the distinctive sound and the Harley-Davidson brand. This design, which is covered under several United States patents, gives the Harley-Davidson V-twin its unique choppy "potato-potato" sound. To simplify the engine and reduce costs, the V-twin ignition was designed to operate with a single set of points and no distributor, which is known as a dual fire ignition system, causing both spark plugs to fire regardless of which cylinder was on its compression stroke, with the other spark plug firing on its cylinder's exhaust stroke, effectively "wasting a spark." The exhaust note is basically a throaty growling sound with some popping.The 45 degree design of the engine thus creates a plug firing sequencing as such: The first cylinder fires, the second (rear) cylinder fires 315° later, then there is a 405° gap until the first cylinder fires again, giving the engine its unique sound.Harley Davidson has used various ignition systems throughout its history--be it the early points/condenser system, (Big Twin up to 1978 and Sportsters 1970 to 1978), magneto ignition system used on 1958 to 1969 Sportsters, early electronic with centrifugal mechanical advance weights, (all models 1978 and a half to 1979), or the late electronic with transistorized ignition control module, more familiarly known as the black box or the brain, (all models 1980 to present).With the implementation of Electronic Fuel Injection (EFI), Harley Davidson uses a single fire ignition system on the models equipped with EFI, which now includes 100% of their product line with the introduction of the 2007 models.In 1991, Harley-Davidson began to participate in the Sound Quality Working Group, founded by Orfield Labs, Bruel and Kjaer, TEAC, Yamaha, Sennheiser, SMS and Cortex. This was the nation's first group to share research on psychological acoustics. Later this year, Harley-Davidison participated in a series of sound quality studies at Orfield Labs, based on recordings taken at the Talladega Superspeedway, with the objective to lower the sound level for EU standards while analytically capturing the "Harley Sound."[citation needed] This research resulted in the bikes that were introduced in compliance with EU standards for 1998.On 1 February 1994, the company filed a trademark application for the distinctive sound of a Harley-Davidson motorcycle engine: "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 comments opposing the application, arguing that cruiser-style motorcycles of various brands use a single-crankpin V-twin engine which produce a similar sound. These objections were followed by litigation. After six years, Harley-Davidson withdrew their trademark application.Interestingly, when Honda first began making a motorcycle with a 45° V-2 design, the Honda Shadow, it used a more advanced engineering approach with an offset crank design which allows for even firing pulses and higher horsepower because of the reduced vibrational stresses on the engine. However, because potential buyers complained that the Shadow did not 'sound like a Harley,' Honda in 1995 introduced the Shadow American Classic Edition (or ACE) which had a single crank-pin design, reduced horsepower and a much more Harley-like sound.



Tidak ada komentar: