Death Wobble
Road Master
Joined: Jun 2008
Posts: 762
Likes: 2
From: Fort Bragg, NC Area
Sorry about your bud.
Did some research on how bikes ride, turn and handle as it pertains to the DW. It is not a clinical answer. Just what I think from what I read and what I know from teaching MSF classes.
When the front wheel and back wheel come out of alignment it causes the bike to do what it is designed to do ... get back in alignment. The only way to get a bike into alignment is to apply power to the wheels. Braking forces the front end down and lightens to rear end. This can increase the wobble since the bike now has nothing preventing the incorrect realignment.
Did some research on how bikes ride, turn and handle as it pertains to the DW. It is not a clinical answer. Just what I think from what I read and what I know from teaching MSF classes.
When the front wheel and back wheel come out of alignment it causes the bike to do what it is designed to do ... get back in alignment. The only way to get a bike into alignment is to apply power to the wheels. Braking forces the front end down and lightens to rear end. This can increase the wobble since the bike now has nothing preventing the incorrect realignment.
Road Master
Joined: Jan 2011
Posts: 945
Likes: 121
From: Where The Bluegrass Grows
My condolences to you and your friends family. Thanks to all who have shared info about the DW. Never experienced one and hope I never do. The experiences shared by those on here who have survived one may save the life of another rider.
Thanks,
SugsPa
Thanks,
SugsPa
Tourer
Joined: Mar 2012
Posts: 343
Likes: 1
From: Western WA
Nels, very sorry to hear about your friend.
Apologies if somebody already posted this link, but saw this a while back via another thread on the DW topic.
http://www.youtube.com/watch?v=Gmw6QppXnEY
Guy doing the riding has some big ones to repeatedly take it to the edge.
Apologies if somebody already posted this link, but saw this a while back via another thread on the DW topic.
http://www.youtube.com/watch?v=Gmw6QppXnEY
Guy doing the riding has some big ones to repeatedly take it to the edge.
Tourer
Joined: Oct 2011
Posts: 331
Likes: 1
From: Glendale, AZ
It's been an issue and commonly talked about at least since the twin cam touring bikes came out in 99. It is a design flaw. I think it's been somewhat helped on the newer frames by the 2 point mounts in the front. The basic design of the tranny/engine being mounted through the swingarm is the same.
Tourer
Joined: Jun 2011
Posts: 316
Likes: 3
From: Under a bridge
What a load of toss, here.
Bikes wobble at low speeds and weave at high speeds, both have separate characteristics. H-D persists in encouraging loading weight over the rear wheel, as 99% of road trip pics will prove. Add to this the wind factor on high or wide 'bars, fork mounted screens.
Mechanically, tyres should be pumped up to recommended pressures, and have plenty of tread, all bearings tightened to correct settings and all nuts & bolts torqued up.
Bikes wobble at low speeds and weave at high speeds, both have separate characteristics. H-D persists in encouraging loading weight over the rear wheel, as 99% of road trip pics will prove. Add to this the wind factor on high or wide 'bars, fork mounted screens.
Mechanically, tyres should be pumped up to recommended pressures, and have plenty of tread, all bearings tightened to correct settings and all nuts & bolts torqued up.
I've had a tank slapper on a sport bike which I attributed it to a "light front end." On those bikes, any lean angle can be a tank slapper with a twist of the throttle. I cleared that tank slapper by pulling the front wheel up, not a viable option on a tourer. I'd compare my experience to a touring bike front wheel being relatively light at high speed and wobble starting in a lean.
Reverend, since this is all a "load of toss" and you are an expert on wobble/ weave, please enlighten us on how to properly "tighten a bearing to correct setting." I have an engineering degree and have been riding and wrenching for over 30 years but I've never been taught how to tighten a bearing. Always looking to learn new things!
Thread Starter
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Road Warrior
Joined: Jun 2008
Posts: 1,343
Likes: 173
From: Watertown, CT
Thank You all for your thoughts. After talking to the other rider who seen the wobble in his rear view I heard from the passengers in the car behind the riders who witnessed the bike going into a violent shimmey and seen the crash. It appears to be a mechanical malfunction and there is a investigation going on now to determine the cause. We will bury my friend Thursday. He will be missed, friends like this are few and far between.
BTW: witnesses said speed and horse play were NOT involved , 45 mph and a very slow curve.
BTW: witnesses said speed and horse play were NOT involved , 45 mph and a very slow curve.
Road Captain
Joined: Jun 2009
Posts: 718
Likes: 0
From: Fly Over Country
My Xstream WIDSHIELD from LongRide Shields made a noticable difference.
from their website, "The Xstream reduces drag from the front of the fairing and gives greater stability when riding along curvey roads"
good stuff.
Cruiser
Joined: May 2011
Posts: 200
Likes: 0
From: Pensacola, Fl.
sorry for your loss. We are all one day closer to the grave every morning when we wake up. Sounds like your friend was doing what he enjoyed.
The harley death wobble is due to a design flaw concerning the swing arm, motor mounts, bushings, etc.. It generally rears it's ugly head at speed in long, sweeping curves. Most riders have felt it at one time or another. We should all pay close attention to our tires, shocks, bearings, bushings, motor mounts, and so forth.
All of the components that go into making a motorcycle are furnished by the lowest bidder...there are lots of things that can be changed on a motorcycle to make it safer and more enjoyable. And yet we keep spending our money on chrome and speed goodies. Might be a lesson to be learned here for all of us.
The harley death wobble is due to a design flaw concerning the swing arm, motor mounts, bushings, etc.. It generally rears it's ugly head at speed in long, sweeping curves. Most riders have felt it at one time or another. We should all pay close attention to our tires, shocks, bearings, bushings, motor mounts, and so forth.
All of the components that go into making a motorcycle are furnished by the lowest bidder...there are lots of things that can be changed on a motorcycle to make it safer and more enjoyable. And yet we keep spending our money on chrome and speed goodies. Might be a lesson to be learned here for all of us.
Cruiser
Joined: Jul 2009
Posts: 122
Likes: 1
I definitely had a "death wobble" on my 2010 Ultra. I was speeding (somewhere near 100 mph) left off the gas......the thing wobbled so badly I nearly could not hold the handlebars. First time in my motorcycle life I looked down on the pavement and thought to myself......this is going to hurt. The bike continued to wobble down to 50 or so and I was safe. Bike had 15,000 miles on it , new tires. Took it to the HD shop the following week and the mechanic said the steering head bearings were not loose and everything seemed fine to him. My '06 Ultra did the same thing but the '10 was much worse.
Extreme HDF Member
Joined: Dec 2007
Posts: 13,402
Likes: 941
From: Illinois
One poster stated that the 09 up frame had the same swing arm.
Absolutely wrong. The new swing arm is a much beefier unit.
I forgot to mention in my last post that there are two causes for problems. A steering wobble is not the same as the swing arm flex and slight deflection from the rubber mounting to the transmission.
Steering wobble is from front tire problems like cupping, front wheel bearings not being adjusted to spec's or worn out. The same from steering head bearings.
Fork mounted fairings/windshields can contribute to steering wobble.
The overloaded touring bikes with flexing swing arms and side to side deflection cause a significant tracking problem not exactly the same as steering head wobble.
Many talk about wobble when in fact there is two types one from front issues and one from rear end issues.
Absolutely wrong. The new swing arm is a much beefier unit.
I forgot to mention in my last post that there are two causes for problems. A steering wobble is not the same as the swing arm flex and slight deflection from the rubber mounting to the transmission.
Steering wobble is from front tire problems like cupping, front wheel bearings not being adjusted to spec's or worn out. The same from steering head bearings.
Fork mounted fairings/windshields can contribute to steering wobble.
The overloaded touring bikes with flexing swing arms and side to side deflection cause a significant tracking problem not exactly the same as steering head wobble.
Many talk about wobble when in fact there is two types one from front issues and one from rear end issues.