Posted on 08/16/2005 7:17:57 AM PDT by yankeedame
There is no denying that a Harley-Davidson motorcycle has a unique sound, especially if the mufflers have been removed! Even with the mufflers on, however, it sounds different from other motorcycles. The reason for the sound has to do with the way the engine is designed. If you have read the HowStuffWorks article How Car Engines Work, then you know how a basic four-stroke gasoline engine operates. A piston goes through the intake, compression, combustion and exhaust strokes every two revolutions of the crankshaft. When your lawn mower is idling, you can hear the pop-pop-pop-pop sound of the individual strokes. What you are actually hearing is the sound of the compressed gases in the cylinder escaping when the exhaust valve opens. Each pop is the sound of the exhaust valve opening one time, and it happens on every second revolution of the crankshaft.
In a two-cylinder, horizontally opposed engine, the pistons are timed so that one fires on one revolution of the crankshaft and the other fires on the next revolution -- so one of the two pistons fires on every revolution of the crankshaft. This seems logical and gives the engine a balanced feeling. To create this type of engine, the crankshaft has two separate pins for the connecting rods from the pistons. The pins are 180 degrees apart from one another.
A Harley engine has two pistons. The difference in the Harley engine is that the crankshaft has only one pin, and both pistons connect to it. This design, combined with the V arrangement of the cylinders, means that the pistons cannot fire at even intervals. Instead of one piston firing every 360 degrees, a Harley engine goes like this:
A piston fires.
The next piston fires at 315 degrees.
There is a 405-degree gap.
A piston fires.
The next piston fires at 315 degrees.
There is a 405-degree gap.
And the cycle continues.
At idle, you can hear the pop-pop sound followed by a pause. So its sound is pop-pop...pop-pop...pop-pop. That is the unique sound you hear!
It also has something to do with the single- vs. dual-pin crank, dunnit?
Nevermind. Pre-cuppa coffee post there.
Morning Martin, enjoy your coffee!!
Dear Cecil:
A few days ago a colleague at work asked me, "Does Harley-Davidson have a patent on the sound of their exhaust?" I thought he was kidding. I never heard of the government granting a patent on a particular sound. Then a friend of mind told me H-D won a lawsuit against one of the "rice burner" bike manufacturers because they had (electronically) duplicated the sound of the Harley! What gives? Can you really patent the exhaust sound of an infernal--strike that--internal-combustion engine? --Jens, Glenview, Illinois
Cecil replies:
Not a patent, Jens. A trademark. You patent an invention; you secure trademark rights in a symbol associated with your company or product. Sure, you can get one on a sound. MGM registered the roar of its lion as a trademark, and NBC registered its three-toned chime as a service mark. Hadn't heard that chime in years, but as soon as I saw it mentioned, it popped into my mind, practical proof that sounds can be potent symbols. Trouble is, when I think of Harley, I think of Hell's Angels, the Harley logo, and the word hog (which Harley also tried to register). But--and I realize this may say negative things about my testosterone level--I don't think of a particular sound, which might explain why Harley withdrew its application to register the engine sound earlier this year.
Harley aficionados, and of course the company itself, see it differently. To them the Harley sound, said to resemble "potato-potato-potato," is as distinctive as the Energizer bunny. (Judge for yourself with the sound clips at newsport.sfsu.edu/archive/f96/s ounds/pending.html). When Japanese motorcycle makers began horning in on the Milwaukee company's hog market with their own heavy-duty bikes in the 1980s, Harley felt they were trying to duplicate the rumble of the V-Twin engine, which buyers supposedly seek out. Maybe, though if you ask me they mostly want something loud enough to scare the crap out of guys in Honda Civics. The Japanese put it more diplomatically when fighting Harley's trademark request, arguing that all big motorcycles sound pretty much the same. After six years of legal proceedings and no resolution in sight, Harley caved, claiming it had won in the court of public opinion, etc. Just as well. Can you imagine the trademark infringement suits?
Harley lawyer: "Your honor, our competitor's ripoff of our product purposely goes potato-potato-potato."
Rice-burner lawyer: "Nonsense, it goes poTAHto-poTAHto-poTAHto. Motion to call the whole thing off."
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DESMO!
It's them beans makes that rumble in the saddle.
If that power source works for you, enjoy it.
I looked at the SV650 recently, but it's gotten pretty big in the latest model (I think it shares parts with the 1000). Plus I had a bad experience with a 600 Bandit. Finally got a Ducati 620 Monster.
Potatos... Lots of potatos!
Personally, I prefer the sound of a 90 degree V-Twin... My Ducati (when I really open the throttle, HARD) sounds alot like a Nascar V8! Of course, it helps that I've got a set of Carbon Tech slip-ons ( I couldn't afford the Termis :-( ) and removed the airbox cover, with a K&N air filter! I've set off car alarms!
Mark
LOL!
Have you seen this? :)
Welcome to the Desmo world!
(These are belt buckles made by Tom Roland - You can read about them here.)
Mark
I wanted something different from my Kawasaki Concours, and boy did I get it!
They certainly have personality, don't they?!?! :-)
Mark
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