How Harley-Davidson Works

100th anniversary harley emblem
Photo courtesy Harley-Davidson Motor Company
Harley-Davidson 100th Anniversary Tank Emblem with Chrome Bar & Shield

How do you write about Harley-Davidson? When someone mentions the words "Harley-Davidson" several things come to mind:

  • The company that produces motorcycles.
  • The actual motorcycles that the company produces.
  • The history and tradition that surround the company and the products.
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And, there's something else, too -- the aura of Harley-Davidson. Some call it Harley mania. Others refer to it as Harley culture. If you're having a hard time understanding this concept, just consider this: Every year, hundreds of thousands of Harley-Davidson enthusiasts converge on towns like Sturgis, S.D. (August), Myrtle Beach, S.C. (May) and Daytona Beach, Fla. (March) for an entire week of partying and vendor demos. These folks ride their bikes hundreds if not thousands of miles just to participate.

Unlike any other major brand of bike, there's a certain something that Harley-Davidsons carry with them. It could simply be the sound of a large V-Twin engine through straight pipes at full throttle -- this has certainly been glamorized in dozens of movies. But we think it's more than that. Call it mystique if you like. There is definitely something to it.

a 2003 Harley Screamin' Eagle Softail Deuce
Photo courtesy Harley-Davidson Motor Company
The 2003 Screamin' Eagle Softail® Deuce, shown here in custom paint colors - Centennial Gold and Vivid Black.
See more motorcycle pictures.

In this article, you will have a chance to learn about the Zen of the Harley-Davidson from a HowStuffWorks perspective. We will cover the evolution of the engines, the current product line and the customization process. The next time you pull up alongside a Harley-Davidson, you'll see it in a completely different way.

Before you can begin to understand the Harley mystique, you'll need to have a basic understanding of how motorcycles work.


­At its very simplest, a motorcycle is a bicycle with an engine. If you go all the way back to the beginnings of Harley-Davidson Motorcycles in 1903, a motorcycle is exactly that. The first production Harley-Davidson was a bicycle with a slightly modified frame to make the engine easier to mount. A leather belt carried the power from the engine to the rear wheel. This motorcycle had pedals, so you could pedal it like a bicycle if you wanted to. It also had a normal coaster brake in the rear hub that you could apply with the pedals (by pedaling backwards), just like you would on a normal one-speed bicycle today.

the first Harley
Copyright Harley-Davidson Archives
Photo courtesy Harley-Davidson Motor Company Archives
The first Harley-Davidson was basically a motorized bicycle.

That original Harley-Davidson motorcycle had a 24.75 cubic inch (405 cc), single-cylinder, air-cooled engine with an F-head valve configuration. The engine weighed 49 pounds.

Today a motorcycle does not really look at all like a bicycle. Both vehicles have two wheels, but that is where the similarity ends. Read on to learn about today's motorcycles.