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[Dan_Lockwood]

Hi to all here.

I've been posting a little around here and have a question.

Since my new '08 SERK isn't in yet and my '76 FLH is down right now getting the crank rebuilt, I've had the pleasure to ride my buddy's '03 SE Duece.  The bike has just over 8k miles on it.

He rode it this year in Sturgis and put on about 1,000 and it handled fine, no signs of a wobble.  Since he's been back, he's been riding his custom bike and I've had the opportunity to ride his Duece a bit. 

I noticed a slight frontend wobble at between 25 to 45 mph.  If it had spoke wheels I'd say it acted like a loose spoke job, but of course it has cast wheels.  The tires are less than a year old and are very good tread wise.  We spun the front wheel on the stand and the tire tracks straight without wobbles or bulges like a split tread etc.

If you let go of the handlebars it will shake in your fingers, not enough to go out of control or anything.

I can't feel anything in the steering head, but could this be the cause of the wobble?  Should we look at repacking the steering bearings and torque the spindle?

Any information or suggestions will be greatly appreciated.

Thanks in advance.

[mrmagloo]

I wonder if the tire/wheel is out of balance? The factory uses those tapes weights which are prone to disappearing. I check the wheel closely for any residue indicating lost weights as an easy first step.

[Dan_Lockwood]

I wonder if the tire/wheel is out of balance? The factory uses those tapes weights which are prone to disappearing. I check the wheel closely for any residue indicating lost weights as an easy first step.

Thanks for the reply but I would think that a bounce would be the result of an out of balance wheel/tire.  This is really like the old radial tires of days gone by that would let the car wobble from side to side at parking lot speeds but would not show any signs of out of balance at speed.

Thanks again for the reply.
 

[djkak]

Hi to all here.

I've been posting a little around here and have a question.

Since my new '08 SERK isn't in yet and my '76 FLH is down right now getting the crank rebuilt, I've had the pleasure to ride my buddy's '03 SE Duece.  The bike has just over 8k miles on it.

He rode it this year in Sturgis and put on about 1,000 and it handled fine, no signs of a wobble.  Since he's been back, he's been riding his custom bike and I've had the opportunity to ride his Duece a bit. 

I noticed a slight frontend wobble at between 25 to 45 mph.  If it had spoke wheels I'd say it acted like a loose spoke job, but of course it has cast wheels.  The tires are less than a year old and are very good tread wise.  We spun the front wheel on the stand and the tire tracks straight without wobbles or bulges like a split tread etc.

If you let go of the handlebars it will shake in your fingers, not enough to go out of control or anything.

I can't feel anything in the steering head, but could this be the cause of the wobble?  Should we look at repacking the steering bearings and torque the spindle?

Any information or suggestions will be greatly appreciated.

Thanks in advance.

You describe a classic “coast down wobble”. The symptoms are when the machine is decelerating, as you pass from approximately 40 mph through 30 mph, the front end and handlebars oscillate. The front end is stable when running outside of the “wobble range”.

My rule of thumb is that if the handlebar grips move less than approximately one inch during the oscillation, I let it go. It has been my experience that excessive coast down wobble is the result of an internal tire malfunction; worn out tire or mismatched tires. With tire malfunctions, there is typically no visible evidence of the malfunction on the inside or outside of the tire.

The issue sometimes becomes apparent after a tire has been changed; this of course makes it easy to determine which tire is causing the problem. In my experience, most of the time the issue is with the front tire; although occasionally I have found rear tires to be problematic. 15 years ago this was a much bigger issue than it is today.

And of course, make sure that all of the appropriate chassis adjustments and torques are in spec before you start throwing tires at the machine.

djkak

[mrmagloo]

Great info. I think I'd be digging into the issue pretty deep way before the handlebars move an inch! I couldn't even imagine how that would feel.

Good luck with sorting this out, but take it step by step and you'll nail it.

[Dan_Lockwood]

You describe a classic “coast down wobble”. The symptoms are when the machine is decelerating, as you pass from approximately 40 mph through 30 mph, the front end and handlebars oscillate. The front end is stable when running outside of the “wobble range”.

My rule of thumb is that if the handlebar grips move less than approximately one inch during the oscillation, I let it go. It has been my experience that excessive coast down wobble is the result of an internal tire malfunction; worn out tire or mismatched tires. With tire malfunctions, there is typically no visible evidence of the malfunction on the inside or outside of the tire.

The issue sometimes becomes apparent after a tire has been changed; this of course makes it easy to determine which tire is causing the problem. In my experience, most of the time the issue is with the front tire; although occasionally I have found rear tires to be problematic. 15 years ago this was a much bigger issue than it is today.

And of course, make sure that all of the appropriate chassis adjustments and torques are in spec before you start throwing tires at the machine.

djkak

Thanks for the information.  Yes it does feel like a tire, like I said what the old radials felt like with the tread seperation from years gone by.

I'll get with my friend over the weekend and we'll get the bike back up on the lift and check it closer this time.

Thanks again for the help.

Just a side note, does any of the Harleys have steering stabilizers like the European bikes have?  I've seen some bike with small light shocks that just fasten to the lower tree and the frame.  Some are adjustable and some just pre-set.  Others have a knob with friction plate on the top of the head spindle that you just turn and tighten the turning resistance.

Does anyone make a kit for the touring family Harley's?

Sorry for the rambling on and on.

[VANAMAL]

MY 02 FXSTD developed the same thing. i replaced the tire and ck the spokes and ask them to balance it close as poss-voila no more low speed wobble. the high speed wobble on the flhtcse is a different story