Constantine Phaulkon
Senior Member
- Joined
- Jan 13, 2011
The well known motorcycle death wobble below. Sympathetic resonance is the mechanical engineering term of art. http://en.wikipedia.org/wiki/Sympathetic_resonance
And apparently it can happen to any bike. Apparently with certain models of Harleys it occurs when saddle bags are used. I've talked to one dirt bike rider who said he happened to him when riding over a certain patch of bumpy ground at a certain speed--the handlebars shook uncontrollably. Of course if the bike is designed well it won't happen very often--thus BMWs say the California Highway Police are better than Harleys (see below).
To paraphrase the American consumer activist, Ralph Naider: "motorcycles, unsafe at any speed?" ;-)
CP
http://www.kpho.com/news/27917754/detail.html
Some Harley Motorcycles Known For Death Wobble
Some Riders Blame Design Of Certain Models
POSTED: 7:19 pm MST May 16, 2011
UPDATED: 11:35 pm MST May 16, 2011
PHOENIX -- The last thing a rider wants to do on a motorcycle is lose control, but that's what some Harley-Davidson riders say happened to them.
To riders such as Vince Herre, the bikes are a status symbol. "I like it just because it's Harley-Davidson," Herre said.
Other riders, such as Cliff Anderson, said there's a certain amount of homegrown pride.
"It's an iconic piece of America," he says.
Riders such as Blake Tomlinson said they think riding a Harley-Davidson is a way of life.
"To drive one is the ultimate sense of freedom," Tomlinson said.
To Jerry Costa, it was only a matter of time before he owned one.
"I had Triumphs, a Suzuki, Hondas and Yamahas. I had all of them before I ever had a Harley," said Costa.
The Peoria biker has been riding for 40 years. "This is my fifth Harley," Costa said.
But no amount of road experience could have prepared Costa for what happened in October along a scenic highway just south of Prescott.
"I wasn't doing anything out of the ordinary. I wasn't doing anything I hadn't done a thousand times before. I had been on that road a couple hundred times," Costa said.
Costa said his speed was about 25-30 mph when, "The whole bike started shaking. I had no idea why the bike was vibrating like that, and it wasn't a little vibrating. I never felt anything like that in my life."
"I got this thought in my head I'm going over the ravine, and I don't want to go down," Costa said.
Costa did go down and was flown to a Phoenix hospital, where he coded and then slipped into a coma. Five days later, he awoke with a quadruple compound leg fracture, eight broken ribs and a punctured lung.
His massive Harley-Davidson Road King was totaled.
Costa blames faulty equipment for the accident, but Harley blames him.
"They say it's operator error," Costa said.
Costa is not alone.
A CBS 5 Investigation found similar incidents across the U.S. The possible equipment malfunction Costa describes has become known as the Harley-Davidson Wobble, or "Death Wobble."
A camera mounted on a Georgia state trooper's police-issued Harley shows Officer Richard Barber traveling 90 mph along an interstate. His 2007 Harley Electra Glide begins to shimmy and wobble. Eventually, Barber is able to stop the bike safely.
But a Raleigh, N.C., police officer was not so lucky. In 2002, 30-year-old Charles Paul was thrown from his Harley Electra Glide after it began to wobble. He died, and his family later settled a wrongful death suit with Harley-Davidson in 2008.
Harleys have been widely used by law enforcement. But the California Highway Patrol decided not to to put their troopers on Harleys after testing the bike by comparing it to BMW bikes. A 2006 test track video shows the Harley side-by-side with the BMW. In the video, you can see the Harley wobbles when heading into and out of turns. The CHP report also says the bike wobbled on the straightaways.
Court cases against the company have centered on these bikes: the Road King, Ultra Classic, the Electra Glide and FLH series. The suits focus on their patented design for keeping the engine mounted to the frame of the bike. Critics argue the system is susceptible to a side-to-side motion, causing a wobble.
Harley-Davidson does acknowledge that its bikes are susceptible to a weave or wobble -- depending on the bike's speed. But they said that this does not cause accidents, and that weave or wobble happens to other bike manufacturers, regardless if it is a Harley or not. Harley also said the wobble problem is worsened when riders add on certain parts and suggests people follow the owner's manual.
Jerry Costa said wobble is what happened to his bike, and it haunts him during his long days in physical therapy, where he learns how to do the simple task of moving his ankle again.
Costa can't sue Harley-Davidson because he's already settled with insurance, but he said he doesn't want a payout.
"That's not what I'm after. I want people to know about this. I don't want more people falling off these bikes," Costa said.
And apparently it can happen to any bike. Apparently with certain models of Harleys it occurs when saddle bags are used. I've talked to one dirt bike rider who said he happened to him when riding over a certain patch of bumpy ground at a certain speed--the handlebars shook uncontrollably. Of course if the bike is designed well it won't happen very often--thus BMWs say the California Highway Police are better than Harleys (see below).
To paraphrase the American consumer activist, Ralph Naider: "motorcycles, unsafe at any speed?" ;-)
CP
http://www.kpho.com/news/27917754/detail.html
Some Harley Motorcycles Known For Death Wobble
Some Riders Blame Design Of Certain Models
POSTED: 7:19 pm MST May 16, 2011
UPDATED: 11:35 pm MST May 16, 2011
PHOENIX -- The last thing a rider wants to do on a motorcycle is lose control, but that's what some Harley-Davidson riders say happened to them.
To riders such as Vince Herre, the bikes are a status symbol. "I like it just because it's Harley-Davidson," Herre said.
Other riders, such as Cliff Anderson, said there's a certain amount of homegrown pride.
"It's an iconic piece of America," he says.
Riders such as Blake Tomlinson said they think riding a Harley-Davidson is a way of life.
"To drive one is the ultimate sense of freedom," Tomlinson said.
To Jerry Costa, it was only a matter of time before he owned one.
"I had Triumphs, a Suzuki, Hondas and Yamahas. I had all of them before I ever had a Harley," said Costa.
The Peoria biker has been riding for 40 years. "This is my fifth Harley," Costa said.
But no amount of road experience could have prepared Costa for what happened in October along a scenic highway just south of Prescott.
"I wasn't doing anything out of the ordinary. I wasn't doing anything I hadn't done a thousand times before. I had been on that road a couple hundred times," Costa said.
Costa said his speed was about 25-30 mph when, "The whole bike started shaking. I had no idea why the bike was vibrating like that, and it wasn't a little vibrating. I never felt anything like that in my life."
"I got this thought in my head I'm going over the ravine, and I don't want to go down," Costa said.
Costa did go down and was flown to a Phoenix hospital, where he coded and then slipped into a coma. Five days later, he awoke with a quadruple compound leg fracture, eight broken ribs and a punctured lung.
His massive Harley-Davidson Road King was totaled.
Costa blames faulty equipment for the accident, but Harley blames him.
"They say it's operator error," Costa said.
Costa is not alone.
A CBS 5 Investigation found similar incidents across the U.S. The possible equipment malfunction Costa describes has become known as the Harley-Davidson Wobble, or "Death Wobble."
A camera mounted on a Georgia state trooper's police-issued Harley shows Officer Richard Barber traveling 90 mph along an interstate. His 2007 Harley Electra Glide begins to shimmy and wobble. Eventually, Barber is able to stop the bike safely.
But a Raleigh, N.C., police officer was not so lucky. In 2002, 30-year-old Charles Paul was thrown from his Harley Electra Glide after it began to wobble. He died, and his family later settled a wrongful death suit with Harley-Davidson in 2008.
Harleys have been widely used by law enforcement. But the California Highway Patrol decided not to to put their troopers on Harleys after testing the bike by comparing it to BMW bikes. A 2006 test track video shows the Harley side-by-side with the BMW. In the video, you can see the Harley wobbles when heading into and out of turns. The CHP report also says the bike wobbled on the straightaways.
Court cases against the company have centered on these bikes: the Road King, Ultra Classic, the Electra Glide and FLH series. The suits focus on their patented design for keeping the engine mounted to the frame of the bike. Critics argue the system is susceptible to a side-to-side motion, causing a wobble.
Harley-Davidson does acknowledge that its bikes are susceptible to a weave or wobble -- depending on the bike's speed. But they said that this does not cause accidents, and that weave or wobble happens to other bike manufacturers, regardless if it is a Harley or not. Harley also said the wobble problem is worsened when riders add on certain parts and suggests people follow the owner's manual.
Jerry Costa said wobble is what happened to his bike, and it haunts him during his long days in physical therapy, where he learns how to do the simple task of moving his ankle again.
Costa can't sue Harley-Davidson because he's already settled with insurance, but he said he doesn't want a payout.
"That's not what I'm after. I want people to know about this. I don't want more people falling off these bikes," Costa said.
