How Harley-Davidson Works

What is a Harley?

the 100th anniversary emblem
Photo courtesy Harley-Davidson Motor Company
Harley-Davidson 100th Anniversary Tank Emblem with Chrome Bar & Shield
You can get all kinds of motorcycles today, mostly from Japanese manufacturers like Honda, Yamaha and Kawasaki. But, most folks would argue that none of them have the aura, tradition, name recognition or mystique of the motorcycles from Harley-Davidson. You're probably wondering what it is that is so unique about a Harley, so let's start with the engine.

Here are some of the distinguishing characteristics of the engine:

  • Until 2001, Harley-Davidson had been devotedly married to the two-cylinder V-twin design with a 45-degree angle between the cylinders.
  • The engines are air-cooled.
  • The engines have overhead valves that are activated by camshafts in the crankcase.
  • Oil comes from a dry sump lubrication system.
  • Harley engines have a long stroke. This means that the engines are low-revving and have lots of torque. Redline is typically in the 5,000 RPM range.
  • Harley engines have a single-pin crankshaft, giving these engines a unique sound. We'll have more on that distinctive sound in the next section.

In 2001, Harley made what was for it a radical move. A new engine called the Revolution™ engine was introduced, to be used in the upcoming 2002 VSRC. The Revolution is still a V-twin but it has a 60-degree V, is water-cooled, has 4 overhead camshafts and is high-revving (9,000 RPM redline).

the Harley Revolution engine
Photo courtesy Harley-Davidson Motor Company
The Revolution™ engine is currently used on only one Harley production model -- the VSRC. Both the 2003 VRSCA V-Rod™ (shown here) and the 2002 VSRC sport the Revolution™ engine.

Beyond the engine, Harley motorcycles themselves have their own look and feel. Because of the big engines, Harleys tend to be big bikes. The biggest Harleys weigh close to a thousand pounds (453.6 kilograms) and tend to incorporate retro styling. We'll discuss the new engine in more detail a little later on in this article.

Next, we'll learn about the Harley mystique and its distinctive sound.

Harley in the Movies
From "Easy Rider" to "The Terminator 2" to "Mission: Impossible II" -- motorcycles have been making the movie scene for decades.
dvd cover of 'harley davidson and the marlboro man'
Photo courtesy
In fact, Harley-Davidson gets top billing in the 1991 movie entitled "Harley Davidson and the Marlboro Man." Featuring two main characters: one named for the famous motorcycle company and the other a popular cigarette brand, this movie continues to have a following. Some other products are also given a nod in the film -- there's a character named "Virginia Slim" (like the cigarettes) and another named after the famous whiskey "Jack Daniels."