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Discussion Starter #1
Have a minor shake of the handle bars when slowing down. Only happens when the road is not completely smooth at about 25-30 MPH. I can only feel it if I do not have firm gripe on bars. Pulled the wheel off other day. Some of spokes were loose. Tightened them by hand, some moved less the 1/16 of a turn rest were tight. I tightened them all by feel not a torque wrench. Bearings felt smooth with no play. Spun wheel with out the caliper on it and never stops at any specific point, so I'm pretty sure balance is good. Tire has about 3k on. Bearings about 7K. Put a dial indicator against rim, showed a max run out of .022 in one area runs .010-.018 rest of wheel. Not correct way to check wheel for run out. Have no clunks and cannot feel any movement in stem bearings. Never been adjusted have 33K on them. After all that shake still there but feels less. Tire pressure 32psig.
Any ideas are appreciated.
 

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Asylum Inmate
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What tires are you running and what mileage on them?

Does it only happen on deceleration?

Does it go away as soon as you put torque to the back wheel?
 

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Just Ride
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Do a fall away test. I'm thinking neck bearings slightly loose . Last time you greased them?
 

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Discussion Starter #4
What tires are you running and what mileage on them?

Does it only happen on deceleration?

Does it go away as soon as you put torque to the back wheel?
New Dunlop on front with 3K on it and while slowing down, check my post. Have to try accelerate when it starts. Im usually coming to a stop light when it happens. No brakes applied.
 

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Discussion Starter #5
Do a fall away test. I'm thinking neck bearings slightly loose . Last time you greased them?
I greased them few years ago with heavy wheel bearing grease. But it seeped out, Should have used what HD recommends ?
Fall away test sounds like a good one.
 

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New Dunlop on front with 3K on it and while slowing down, check my post. Have to try accelerate when it starts. Im usually coming to a stop light when it happens. No brakes applied.

I found a really strange problem on my FLSTFB with the stock dunlops. There is an oscillation that forms around 4k miles on the tires.

I switched to MC II and it stopped until 8.5K

I then switched to Avon Cobra and it never came back. They ran 6500 miles before they hit the wear bar.

I now have 3K on a set of Dunlop American Elites. So far no decel oscillation.

I never put the bike in Solid Works to look at the design, but I suspect it is a harmonic that shows up with those dunlops and the way they wear.

I have had two other guys complain about it, tire switch took care of it.

Use marine lower unit grease or boat trailer wheel bearing grease on the neck. Damn nice grease. I have found you can dampen it by tightening the fall away but only for a short time and you will still feel it there... Just a lot less amplitude in the oscillation.
 

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I found a really strange problem on my FLSTFB with the stock dunlops. There is an oscillation that forms around 4k miles on the tires.

I switched to MC II and it stopped until 8.5K

I then switched to Avon Cobra and it never came back. They ran 6500 miles before they hit the wear bar.

I now have 3K on a set of Dunlop American Elites. So far no decel oscillation.

I never put the bike in Solid Works to look at the design, but I suspect it is a harmonic that shows up with those dunlops and the way they wear.

I have had two other guys complain about it, tire switch took care of it.

Use marine lower unit grease or boat trailer wheel bearing grease on the neck. Damn nice grease. I have found you can dampen it by tightening the fall away but only for a short time and you will still feel it there... Just a lot less amplitude in the oscillation.
Been running stock Dunlops on front since day one. Average wear 7k plus with no issues. This Dunlop has a new tread design
from the others. HD is running it on all the new bikes with similar size as my FXSTC. Have 33K on bike and it has always run smooth as silk till this tire change and found some loose spokes. Like you mentioned it could be tire issue. Should get fall away test done.

Have to check out that grease.

Thanks for help. Ride Safe
 

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Discussion Starter #9
Do a fall away test. I'm thinking neck bearings slightly loose . Last time you greased them?
Thanks for your input. I will check things out. Ride Safe
 

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I've seen and had this particular problem on so many different makes and manufacturers that I don't believe it's just a Harley problem. My best uneducated guess is the way a particular tire wears over time.
 

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Discussion Starter #11
Billy... this is one of the threads where we went through the shake thing.

So many things can cause a shake in a bikes front end, but this IMO is an engineering cause.... and I think it has to do with the softtail (FLST) design.

http://www.harley-davidsonforums.com/forums/softail-general-discussions/53334-2013-fb-lo-shakes.html
Hey Marine I read the thread you suggested. I get the cause is mostly the tire or neck bearings. As I said before, ran same stock Dunlop as it came from factory. Really considering this Dunlops new tread design could be causing it. Does feel a little better during quick maneuvers. I did not mention I have a HD Fork Brace gives me more feed back in turns. I installed it with old tire prior to this one, not see this contributing to my problem.

My dad was a MARINE 2nd. Division.
 

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My dad was a MARINE 2nd. Division.
Hope it helps, it is a goofy little tick that shows up. Funny mostly with dunlops and a really worn out MC II.

I was 1st Division... west coast...... Semper Fi to your Pops!
 

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Discussion Starter #13
I was 1st Division... west coast...... Semper Fi to your Pops!
Dad is gone but Im sure he would say Semper Fi back at you. :thumbsup
 

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Billy... this is one of the threads where we went through the shake thing.



So many things can cause a shake in a bikes front end, but this IMO is an engineering cause.... and I think it has to do with the softtail (FLST) design.



http://www.harley-davidsonforums.com/forums/softail-general-discussions/53334-2013-fb-lo-shakes.html

I don't believe it's bike or engineering, cause it's fine after tires are new for a while. Id look more at bearing, spoke area


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Discussion Starter #15
I don't believe it's bike or engineering, cause it's fine after tires are new for a while. Id look more at bearing, spoke area


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Have to agree with you. The bike has been flawless till this came along. In wide open desert runs cruising sometimes 80mph. She just hums along wearing out the tires.. :) Thanks for info every one.
 

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I don't believe it's bike or engineering, cause it's fine after tires are new for a while. Id look more at bearing, spoke area


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I don't agree.

I believe it has something to do with how the forks load on deceleration. Causing a low amplitude wave. This is causing an unusual wear that starts to increase the amplitude of the wave and exasperates the problem.

Also has something to do with the compound of rubber.

But I cannot prove it yet. So every answer is valid.
 

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Discussion Starter #18
Had time to go out try replicate handle bar shake. 40-35 something is there but not much. Depends on road surface, smooth practically nothing. Irregular surface and it is slightly more pronounced. Tried accelerating out found it hard to do it that tight a speed range, feels like it may go away. Back to square one. The tire or neck bearings. I will go check those spokes again just because. Have good weekend every one.
 

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If you end up buying new tires I will pay to have those old ones shipped to my lab so I can test them.
 

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If you end up buying new tires I will pay to have those old ones shipped to my lab so I can test them.
Your really into this. I have my old wheel and worn out tire still mounted. Been considering putting it back on to test for shake. If I put old one back on and shake goes away may take you up on that. Bearings are little rough on that wheel, hmm. In case your wondering found this other wheel with disc on Ebay for $50. Hard to pass up.

I need a rear tire before replacing the front. Running a Michelin CMDR II, great tire all around.
 
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