Air in the suspension should be checked.

Tires are the first thing to replace if the date codes are older than two years.

The steering head bearings should be checked and possible re-packed and tightened to spec.

Motor mount check on all mounts including swing arm.

If that doesn't get rid of it the stabilizers should nix any remaining wobble.

 

I am in no way questioning your riding ability or technique, I would just like to point out something that is very important and very helpful to any motorcycle rider.

You may already know this but, after you have checked all those items listed above which are also very important, read and understand what counter steering is.

Many years ago I experienced the "death wobble" in a curve and it freaked me out. Went to the dealer asking what might be wrong with my bike. The service tech checked out my bike and everything was fine and he also asked me if I practice counter steering, I didn't know what he was talking about. After that explanation and actually practicing it it was an eye opener.

 

Also very important that I've not seen mentioned in this thread: Check your FRONT motor mount. When they go bad, it will feel like the rear is not stable. Counter intuitive, but true.

The material in those mounts degrade over time, and the mount donut through 2006 is well known to having a tendency to shear in half, like a sliced bagel.

The updated HD replacement part has improved material, as do aftermarket ones, I'm sure.

 

I have never been able to do a "clean" oil filter change, no matter what precautions I have taken. On a bike that old, oil spilled on the front engine mount has had years to slowly destroy it. I suspect that tires and a front engine mount will be your first big expensive add-ons to the purchase price. There are as many opinions about tires as there are people in the forum. You will have to decide if you want sticky, high traction tires (wear out quickly) or harder, long mileage tires that don't have quite as much traction. I don't try to make a touring bike behave like a cafe racer, I go with the long wear option.

 

Personally, I run no less than 40-45 psi in the rear shocks. But, I really don't think that's your problem. Sounds like the old "tank slapper" which can happen on any motorcycle, not just HD's. This is an EXTREMELY SERIOUS condidtion + if you can't find someone to solve it, I'd unload the bike! I had a bike did this in hard sweepers + you can't power thru it, power down outta it, nothing. This has taken down some of the best riders on the planet, I'm talkin motorcops, so unless you're a better rider than them, fix/unload it. Don't mean to scare anyone...but this is SERIOUS!!!

 

I'm almost positive but the older air suspension max psi is less than the newer models, check to see what the max pressure is on your older bike.

 

It's scary, but common on the older touring bikes (my 2005 RK did this in a scary way...). The fix for me was replacing the swing arm bushings/mounts, and adding a rear/chassis stabilizer (not cheap, but worth it). This, of course, after checking tire pressures, etc. This fixed the problem. My '98 RK has one, and it handles like a champ. It isn't a "get rid of the bike" thing, but rather another weak point that needs addressing. My .02

 

If anyone reading this thread has not read, or better yet taken the course, you NEED to know Lee Parks Total Control book/class like the back of your hand. I have had numerous close brushes with losing control of my machine. I've had wobbles, critters, cagers even pedestrians try and take me out. I credit Lee Parks for NEVER having gone down on a road bike. I am 53 and have owned a road bike since I was 20. Taken plenty of classes. I still know that any day might be the day....but I doubt it! I practice, practice, practice and therefore, nothing surprises me. Total Control...thanks Lee!

 

P.S. and really...not to be a dick, but if you have never heard of counter steering and do not practice it EVERY time you ride...please sell you motorcycle and get a scooter because that is DAY ONE stuff.

 

Agree with most...,check everything according to manual. Make sure tires are good and properly inflated. Still wobble??? Tru Trac should solve.put on my 13 Street Glide and haven't had an incident with CE.