Had it happen only once on my 01 Roadglide. It was a tire problem. Not sure if the belt shifted or what, but new tires corrected the problem.

 

Break your motorcycle down into it's basic components. 1. A rigid welded frame surrounding the motor/transmission & extending back to support the rear fender. 2. A telescopic steering assembly attached to the frame by a metal bearing & bolt assembly. 3. A rear sub-assembly used to hold the rear wheel & attached to the frame by rubber bushings in the swing arm & the shocks. You can see the motor move on the front rubber mount at idle. The movement at the rear mounts is more difficult to see, but it's there. For it's intended purpose (isolating the vertical vibration of the motor from the frame) the system performs it's job very well. The problem arises because those same rubber mounts allow horizontal movement as well as vertical. If you understand frame geometry & counter steering you can easily see why keeping the wheels aligned in turns is important, & why allowing the rear sub-assembly even a tiny deviation in alignment will induce instability. The rubber mounts at *both* ends of the motor/transmission contribute to the "flex" in the frame/sub-assembly. That flex & several other conditions *can* result in "wobble". Limiting the flex gives you a more stable ride at all speeds, & allows you to concentrate on the other maintenance issues to prevent "wobble".

 

Yeah, these guys crack me up. Guess I should have used the official "guy eating popcorn" smilie.

 

There are several ride stailizing kits out there. One is at terrycomp.com. The problem is with a rubber mounted engine, the engine is trying to stay strait up as you roll into a turn so your feeling the engine fighting the frame.

 

Thanks Jinks and all who responded with helpful input and responses!

 

Here's what the Harley Tech told me about it at the Rapid City Convention Center, during the Sturgis Bike Rally a couple of years ago. Just the messenger here.
1. Too much loaded on the bike, i.e. carrying over capacity.
2. Too much speed, i.e. either in long sweepers, or bumpy highway conditions.
3. Cause is multiple, i.e. tire pressure, front bearings, swing arm bushings, frame flex, etc.
4. Effects are caused as the frame of the bike actually flexes from the stress put on it while in the above conditions. The wobble occurs because the bike is trying to straighten itself back out of the flex mode.
5. His bottom line: (Which I thought was kind of a wise azz response) Slow down, and don't pack so much crap while riding.
6. If you haven't experienced the notorious wobble, perhaps you're riding the correct speed, and not overloaded, at least he said that contributed to experiencing it.

We've all read a ton about the fix, but that was Harley's party line at the Convention Center in Rapid City, from the Harley Technician that talked to me about it. Just the messenger here. Please don't shoot.

 

This answer is side-stepping the correct answer, blaming it instead on everything from tire pressure to riding style. Yes, tire pressure is important, but that isn't what's causing the behavior we're talking about.

First, a heavier load does accentuate the waggle, but it will occur with no additional weight at all and without a passenger. Exactly what is "too much speed"? I suppose if we all rode at 35mph around every sweeper we would never have the problem, but reality is something quite different. You can generate a waggle at even a relatively slow speed with enough suspension bouncing in a sweeper.

This is part of the problem, and even with a stabilizer you will feel some flex, though not nearly as much as in a stock configuration. I would say 95% disappears with a stabilizer, which points to the swingarm bushings as the primary culprit.

Very wise-azz, unrealistic, and stupid--skirting the real source of the problem. Not you, I'm talking about the freakin' tech's response.

FWIW, '09s have little of the flex/waggle problem because the frame is sturdier and the motor mounts are redesigned. I haven't ridden an '09 yet but everyone who has says they are a big improvement.

 

So far (since I started this response), Jinks is the only one to mention the word "alignment" and I feel this is the key component.

If the tires are okay, and your bike is properly aligned, this phenomenon should not present itself to any great, or even barely noticeable degree.

If your vehicle is not in proper alignment, the front wheel, the steering neck, and the rear wheel will not all be in-line with each other as you go down the road. The wheels will align themselves to be travelling perfectly into the direction of travel, but if they are not in physical alignment on the frame, they will now be travelling in different tracks down the road. When you are operating this way and hit a bump, you will get the front/rear motional response, but there will also be a side-to-side motional response, where first one "side" of the bike, then the "other" will traverse the bump. When this happens, the handlebars will wiggle.

It's not so bad when you're going straight down the road, but a wiggle in the handlebars while leaned into a curve will (up)set other things into motion.

All these braces help to minimize the after-effects, but they do nothing to prevent them from happening. If you prevent them from happening, the braces become much less important.

I say less important because, due to the construction of the rolling chassis, as already discussed above, there will always be a little more "give" in the assembly than might be ideal. These braces help to reign in some of that "give", and there's no denying that would be a good thing. I'm just saying it's not as important as careful attention to detail in the alignment in the first place.

In the '07 Touring shop manual, it gives a tolerance for the wheel track at 1/16". If your handlebars are square in their mounts and the front end isn't tweaked, your handlebars should be square to the bike as it goes straight down the road. If the bars aren't square to the bike and the front-end stuff is good, that means your rear tire is tracking to one side (the side they're pointing to).

The '09s have front motor mounts similar to the rears, for a 4-point system down low, with a fixed link up under the steering head to lock the assembly vertically in the frame.

Prior to that, there is only one motor mount in the middle front, with an adjustable link to align the motor/tranny/swingarm laterally in the frame, and an adjustable link either under the gas tank, or under the steering head ('08) to handle the vertical alignment.

You can't (readily!) just adjust one, then finish with the other, in one change each. You usually have to walk them into place alternately, in small steps, until they both arrive where they need to be together.

Alignment is the best thing to do first. If afterward you still have some "wallowy" issues you want to address, then choose one of the rear braces.

 

These baggers engines are rubber mounted, and the swingarm is mounted through rubber bushings at the back of the trans....They can't help but have a little lateral movement and that causes a slight "wobble" or "rear steer".
I put on a bagger brace and it eliminated it 100%.
There are several but I chose the Bagger Brace and it's a little cheaper too.
http://bitchinbaggers.com/products/bagger-brace/
Mark

 

Go to Engine/Fuel/Intake/Exhaust section in the Tech group of this forum, under 'Sound postings of exhausts'. I think it's the last page, 'cause I put it up just last week. I'm going to edit the clip in the next week or so.

quote=Mississippi Bagger;3984705]Hey CN,

Do you have a sound clip of your bike with the exhaust in your sig pic?[/quote]