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Discussion Starter #1 (Edited)
Last night, around 20:00 hours, eastbound on highway 403 in Ontario, while travelling in a car around 70 mph (110 kph), a Harley Road Glide came at a faster rate of speed in the passing lane, and came in quite aggressively just ahead of me into the Grandma Lane. Well...while he was still on a 50 degree angle to my travel, merging into my lane, I saw his whole back end of the bike, start to oscillate, back and forth, that started to cause his front forks to start wobbling and oscillating. I hit my brakes, backed right off, and waited for the outcome. He was fighting an ever increasing and stronger oscillation at his back tire, when he put the juice to the rear wheel, and perhaps the straight in-line torque from the open throttle, gave traction and foot-plant to the tire, and the wobble grew less severe, and the front end quieted down.

This was the infamous Harley Death Wobble...and i got to see it in action. Google that phrase and read all about it. I saw it...and it's not urban legend. It is a real happening! As a result, I would never get aboard one, even if I had the chance, let alone now, buy one. Before getting the SVTC, I did go in and price out a Road Glide...(geez!) Sorry...but what I saw nearly made me need to change my shorts...let alone, what must have been happening in that Harley Rider's jeans....

Folks...the Harley Death Wobble is real....and I saw it in action with my own eyes. I don't ever want to see that again...especially it starting to happen 30 feet in front of my car!

http://www.azfamily.com/story/14896060/some-harley-motorcycles-plagued-by-death-wobble-5-16-2011
 

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credit to you for hitting the brakes

a lot of people see an accident happening right in front of them, get mesmerized, and then join in the fun!
 

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Discussion Starter #4 (Edited)
credit to you for hitting the brakes

a lot of people see an accident happening right in front of them, get mesmerized, and then join in the fun!
There were three cars behind me....the first about 65 feet back. I tapped my brakes three times, and then started aggressively braking. I then, when about 30 mph...turned on my 4 ways. He never went down, thank god....but for the last few second of the 'wobble'...it sure looked like he lost it. What saved his *ss, was throttling right up...and that (in my view) put torque and downward thrust onto the back tire...and helped him regain control. I have to tell you...it scared the s*it out of me WATCHING it, as a fellow rider, let alone being on that saddle!

I have owned many bikes, and I have never seen the like of it, either riding, or in anybody else around me on cruisers, sports bikes, whatever....it's not something you'd ever want to feel, start happening to you. All the guy did was pass me, and then lay into a lean as he tried to enter the Granny Lane about 40 feet ahead of my car. He did not have a blow out on either the back or front tire. The back end of the bike just started going into a fierce oscillation, and then long cycle wobble....
 

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some HDs were made with the rear suspension rubber-shock mounted with the engine, to reduce vibration to the rider.

that allows the back wheel to squirm side to side. I believe they have stopped doing that, and you can get steel mounts to replace the rubber ones on the bikes that have them - off the top of my head.

wobble is a serious issue - I dont think any Vstar bikes have an inherent wobble, but you can create one by loading your bike in a way that makes the front wheel top out on its shocks... like putting a trunk suspended behind the passenger sissy bar, and loading it up with 100 lbs of crap.

In the MSF course I was told anything you carry on your bike should be within the triangle from your head to the two axles, which is really a way of saying motorcycles are not stable with a lot of cargo strapped on .
 

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Discussion Starter #6
some HDs were made with the rear suspension rubber-shock mounted with the engine, to reduce vibration to the rider.

that allows the back wheel to squirm side to side. I believe they have stopped doing that, and you can get steel mounts to replace the rubber ones on the bikes that have them - off the top of my head.

wobble is a serious issue - I dont think any Vstar bikes have an inherent wobble, but you can create one by loading your bike in a way that makes the front wheel top out on its shocks... like putting a trunk suspended behind the passenger sissy bar, and loading it up with 100 lbs of crap.

In the MSF course I was told anything you carry on your bike should be within the triangle from your head to the two axles, which is really a way of saying motorcycles are not stable with a lot of cargo strapped on .
Good info to think about. This guy had no top trunk, but two hard panniers, and a frame mounted OEM faring. I'm sure, he also has picked up on the way home, a package of underwear...!!! ;)

Anyway...time to get off the 'pute....get into the shower....pack the bike with lite nylon riding jackets, our Frog Tog bags...two water bottles, her second set of whatever shoes Dee-Dee likes to swap out into...and off for the weekend.
Have a great weekend yourself...for it's gonna be hot...but sunny until Monday morn, at least around the Great Lakes! :)
 

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Proper tire inflation is also very important. Even a few PSI down can completely alter the handling. I can tell if I am more than three PSI down on the rear tire of my Stratoliner. She starts feeling a bit loose in the rear. This is magnified by the fantastic Pennsylvania roads that I get to ride on.
 

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Last night, around 20:00 hours, eastbound on highway 403 in Ontario, while travelling in a car around 70 mph (110 kph), a Harley Road Glide came at a faster rate of speed in the passing lane, and came in quite aggressively just ahead of me into the Grandma Lane. Well...while he was still on a 50 degree angle to my travel, merging into my lane, I saw his whole back end of the bike, start to oscillate, back and forth, that started to cause his front forks to start wobbling and oscillating. I hit my brakes, backed right off, and waited for the outcome. He was fighting an ever increasing and stronger oscillation at his back tire, when he put the juice to the rear wheel, and perhaps the straight in-line torque from the open throttle, gave traction and foot-plant to the tire, and the wobble grew less severe, and the front end quieted down.

This was the infamous Harley Death Wobble...and i got to see it in action. Google that phrase and read all about it. I saw it...and it's not urban legend. It is a real happening! As a result, I would never get aboard one, even if I had the chance, let alone now, buy one. Before getting the SVTC, I did go in and price out a Road Glide...(geez!) Sorry...but what I saw nearly made me need to change my shorts...let alone, what must have been happening in that Harley Rider's jeans....

Folks...the Harley Death Wobble is real....and I saw it in action with my own eyes. I don't ever want to see that again...especially it starting to happen 30 feet in front of my car!

http://www.azfamily.com/story/14896060/some-harley-motorcycles-plagued-by-death-wobble-5-16-2011
Seen all the videos including dash cam footage of bad wrecks happening because of DEATH WOBBLE. It’s VERY real, but in fairness I’ve only seen it on OLDER HD’s (2012 or older) or ones that have been highly modified such as raked choppers etc.
 

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Although one of the names given to this event is the Harley Death Wobble it's also known as high speed wobble or weave, tank slapper and a few other names. It's not exclusive to HD's and can happen to almost any bike under the right circumstances. The recommended way out is to get your body as low as possible and ease off the throttle. Increasing speed typically makes it worse. I've experienced this on two bikes one of which was a Yamaha. The Yamaha was caused by raked front trees which threw off the trail.

https://youtu.be/z3OQTU-kE2s
 

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Although one of the names given to this event is the Harley Death Wobble it's also known as high speed wobble or weave, tank slapper and a few other names. It's not exclusive to HD's and can happen to almost any bike under the right circumstances. The recommended way out is to get your body as low as possible and ease off the throttle. Increasing speed typically makes it worse. I've experienced this on two bikes one of which was a Yamaha. The Yamaha was caused by raked front trees which threw off the trail.

https://youtu.be/z3OQTU-kE2s
That may be an old video. But it’s very informative. ANY bike that is not properly loaded, or with worn & underinflated tires can experience wobble at the right speed. It just so happens that MOST of the instances of this issue have been reported associated with Harley’s.
The video shows other bikes experiencing it which is good to note. Never assume it can’t happen to you & KNOW what to do if you experience it.
 

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That may be an old video. But it’s very informative. ANY bike that is not properly loaded, or with worn & underinflated tires can experience wobble at the right speed. It just so happens that MOST of the instances of this issue have been reported associated with Harley’s.
The video shows other bikes experiencing it which is good to note. Never assume it can’t happen to you & KNOW what to do if you experience it.

Yes, probably due to the volume of HDs on the road as well as more knuckleheads (pun intended) on HDs.
 

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I have never experience a death wobble/tank slapper/underwear changer. And hope I never do!
My front tire hit some gravel in a turn and that scared me enough! And I was only going 15mph.
 

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It is real and I will not argue that. It USUALLY comes into play when a HD is loaded wrong and they make an aggressive maneuver. Not saying that is the case all the time... Like in the video the guy had the rear of the bike loaded down hard. You can see the suspension squatting. If he has air ride it was set too low. There is a kit available that prevents this and is very easy to install.
 

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An improperly loaded and set up bike, doesn't matter the make, is not good decision making and can lead to bad outcomes. Death wobble, etc.
Absolutely. I have experienced wobble only once in my life. Was on my 91 Venture Royale 2 up, loaded down and pulling an 18 cu.ft. Trailer loaded with camping gear and a 48qt cooler on a 21 day 8 State tour. I think just like the videos we’ve seen there was a speed point where the wobble “kicked in”. I was doing 85-90mph trying to outrun some serious weather headed our way.
When it happened I let off the throttle, leaned forward and started to do a purposeful slow weave. She smoothed right out and when I kept my speed to 80mph tops, I never had another issue.
It admittedly had a SERIOUS pucker factor!!
 

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one thing that will set up a wobble on any bike is loose cargo (or a 48 qt cooler nearly full of water), that can move around on the bike

if the bike goes one way, and the cargo goes the other, there is no stable position for both at the same time.
 

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one thing that will set up a wobble on any bike is loose cargo (or a 48 qt cooler nearly full of water), that can move around on the bike

if the bike goes one way, and the cargo goes the other, there is no stable position for both at the same time.
The cooler was full of ice and food, no water. Also it was secured in the cooler rack. Same thing with the cargo in the trailer. Everything had to be a specific place and orientation for everything to fit properly, so there was ZERO load shift.
 

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^ good deal, that is the way you have to do it.

Anything that can move or sway or lean or slosh can setup an oscillation on a motorcycle.

Years ago I worked on the flight control design for military aircraft. Jets like the A10 with the engines on the tail, had so much mass back there that when you turned the jet and then held the controls centered, the tail of the aircraft would twist side to side just from the engines causing the airframe to flex, with a damped 8 hz resonance.

I tried to find the diagram for loading up a motorcycle within the triangle formed by your helmet and the front and rear axles. Ideally you want the majority of the mass on the bike to be in the center of that triangle.

Putting weight behind the passenger seat gives that cargo a lot of leverage to torque the bike from side to side. If you make a sharp correction to the steering, and that weight back there starts moving left and right it can end up with the grips slapping the tank.
 
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