by Tim Cigelske
August 12, 2003
MILWAUKEE — A leather glove twists the throttle, and the unmistakable growl of a revving Harley-Davidson thunders through the air, creating an aura of power, patriotism and the freedom of the open road.
“The sound is one of the distinctive things that makes a Harley a Harley,” said John Schaller, president of the dealership House of Harley-Davidson in Milwaukee.
Harley spent six years trying unsuccessfully to trademark its engine rumble, which would have joined the NBC chimes, AOL’s “You’ve Got Mail” greeting and the Harlem Globetrotter’s theme song as one of the few federally protected sounds. The motorcycle maker withdrew its application in 2000 after opposition from other bike makers.
The syncopated sound – often described as “potato, potato, potato” – is produced when two spark plugs fire nearly simultaneously, followed by a brief pause after the second fire, Harley’s communications director Steve Piehl said. Spark plugs in most two-cylinder engines fire at regular alternating intervals.
The actual noise comes from hot gas escaping from exhaust valves, Piehl said.
“It’s very similar to a heartbeat, which is why I think people tend to like it a lot,” he said. “It gets in your soul.”
The sound – some call it noise – will be multiplied by tens of thousands as bikers roar into Harley’s hometown to commemorate 100 years of the bikes.
Harley expects the four-day celebration beginning Aug. 28 will draw at least 150,000 people to southeastern Wisconsin, although Milwaukee tourism officials put the number closer to 300,000.
A century after the first bike roared to life, the thunderous Harley noise remains annoying to some but fundamental to many bikers’ identities.
“It’s become the patented Harley-Davidson sound, although many other machines have the same sound,” said industry analyst Don Brown, president of Irvine, Calif.-based DJB Associates. “Harley has sort of coined that as their own, and they’ve used it adroitly in their public relations.”
Brown said shrewd marketing directed at middle-aged baby boomers’ nostalgia for Americana made Harley a success story. Harley touted its sound as part of an all-American image in the early 1980s because it had no other way of competing with smaller, high-tech Japanese bikes, he said.
As Harley-Davidson grew internationally leading up to the 1990s, increasingly stringent noise laws threatened the company’s future.
So, in 1991, the company partnered with a Minneapolis-based acoustics laboratory to undertake the delicate task of appeasing non-riders without alienating those who came to identify the sound with all things Harley.
Steven J. Orfield, president of Orfield Laboratories, spent years directing tests of the Harley sound and evaluating Harley riders’ comments. He recorded motorcycles speeding around racetracks with microphones in mannequin’s ears.
Orfield broke the sound into several components, and found that the bikers he worked with liked some aspects of Harley’s signature sound but not others.
He can’t say which pieces of the sound were unpopular – that’s a trade secret.
To keep the Harley sound intact without violating noise laws, Orfield told Harley it could amplify its “good” sounds and mute its “bad” sounds.
The sound’s magnitude has as much to do with the muffler as it does with the engine, said Schaller, of the House of Harley-Davidson.
Schaller said although Harley tweaked its design to comply with government regulations, riders often alter the manufacturer’s product with new parts to create a more robust sound. Many bikers argue that “loud pipes save lives.”
“It’s based on the belief that if you’re coming up on a car on the freeway, your sound increases awareness so that people hear you even if they don’t see you,” Schaller said. “That’s one of the reasons trains have such a loud horn.”
Ted Rueter, director of New Orleans-based Noise Free America, says there’s no evidence to support that argument.
“They do it because they love making noise,” Rueter said. “Why don’t Honda’s all come up with loud pipes so they don’t get run over by SUVs?”