I have posted this before, and I am sorry it is so long but I am sure it will help you out.

I have an 07 Ultra. Right after the 1000 mile service while I was “testing it out” I about dumped it in a long sweeper at 85 MPH. Having been on race bikes that wobble I justput more weight onmy feetand it came out OK. At first I thought it was a front end issue but with further study I believethe issue is“rear steer”. On my ultra it happens at any speed above 80 mph as you lean hard into or out of a sweeper. On the straights it is harder to find but it is still there, just waiting to surprise me.

I stopped at the dealer on my way home and talked to the service manager about it. He called it the bagger boogie and checked the steering head and the swing arm for me. He ask me about the speed and what I was doing to “make it happen” and what I did to come out of it. He said it was not a sport bike and if I wanted it to handle like one I would never be happy. He suggested I try to tune it out or buy a Ride STR8 or TrueTrac.

I have found several things can be done to “tune it out”. I started with tire pressure, by changing up or down a few psi, I can change the speed where it starts and how bad it gets. I also looked at adjusting the air in the shocks, changing my riding position and putting weight in the bags. I now have a very good feel for my bike and how it handles different input from me. I am happy with it but I am also careful when I start pushing the speeds. I think I will end up with either a Ride STR8 or TrueTrac.

I turned up this very well written answer http://www.answers.com/topic/speed-wobble

If you read to the bottom you find the answer that always worked on my race bikes and works well on the ultra too;
Lifting body off the saddle: Lifting the body up from the saddle completely alters the dynamics of the feedback system and the moments of inertia. In particular, lifting yourself off the saddle eliminates the jelly effect.
Just that small tip has kept me on the road more than once. Nothing like a good tank slapper on a fast bike to make you think twice about your tire pressure.

-eleven

 

If the engine is an 88B it's balanced, 88A is not. The touring line is not balanced.

 

Good tip, elevenbravo. Now if I can just remember it when it happens!

 

As you said you were comming back from Sturgis, If you load up the tour pak inside and on the luggage rack, you willloose a lot of weight on the front tire,By loading up the back of the bike it will lift the front. Been there done that , bought the T-shirt,,,when I had mine loaded up , I could pickup the front end no problem, but not loaded no way.

 

Air in shocks, balance of load, balance of front tire.......................

 

Were you still drunk from partying the night before at Sturgis?

 

A bud of mine had the same problem. We found his rear tire was not set properley, had a 3 degree offset. We used long floresent light bulbs to aline his wheels. Problem solved.

 

I would start with the following checks.

Tire pressure
Wheel balance
Wheel alignment
Steering neck tightness / bearings
Wheel bearings
Rear swingarm bushings / components


I have found I can induce a wobble on my 06 Ultra if I change the suspension loading while in a turn by using braking or changing power. The road surface can contribute to the wobble. Powering out of the turn seems to add stability.

The wobble will usually only occur at 90 mph and above.

 

Ok gotta ask, how?

 

Off balance load and\or Tire Pressures and cause it...