Honestly......I haven't a clue. Softer sidewalls should flex and hold better? I guess I should have stated that the tire pressure is something I have read on here in a few older posts. One poster recently said he went to his dealer to complain of wobble and they reduced his TP and said "problem solved."

I do not put much stock in it making any difference but since the 36/36 is recommended pressure (I ride 90% of time 1-up) I think I will try it.

 

Never noticed it on my old '06 Road Glide.

 

Actually experienced the REAL WOBBLE from the swing arm issue.

I rented an '09 FLHTCU and thought it was a dream bike until I went into a right hand corner. I felt comfortable with the speed and the lean having taken a few left handers.

What I experienced was a very un-natural rear swing arm shift causing an extremely un-stable wobble going into, around and out of the corner.

All day I tested this issue and I swear it was consistently wobbling on all right hand cornering.

I took the bike back to the dealers and mentioned their rental had an odd issue while making right hand corners and they didn't say a word.

Wasn't until I talked to several other long time Harley riders that my noticing an issue with right handed turns and the swing arm wobble that I was told this is an issue from the factory and that there are aftermarket bushing to cure the trouble.

Now I'm just passing on what I felt and what I was told.

 

The problem usually manifest itself when the bike is fully loaded in the suspension. By that I mean the combination of load weight and G-force bottoming out the suspension. Speed is the most contributing factor for this to occur. This forces the flexing in the rear anchor point of the motor. Yes, tire pressure can effect handling but, for this problem it's mostly full compression of the suspension.

 

It has only happened to me once, I was on an entrance ramp to an interstate, the ramp had a left hand sweeper turn, I was aggresively increasing my speed to bring me up to approx 80 MPH, the normal speed of this interstate. This entrance ramp had the ice grooves ground in it and I'm sure that I had cut across some of them that caused the resonate frequency that it took to trip the wobble off. I've been on that entrance ramp many time before and after that being careful never to hit that resonance again, I thought I was going to lose it as I entered that busy interstate.

I think the common link here from everyone's experiance is riding aggressivly. Believe me, when those handle bars wanted to whip from side to side at several times per second, you require all the strength you have to minimize that until you slow down (or possibly speed up, someone else can try that) to get out of this resonance issue, especially when in a curve. I'm no longer as aggresive as I once was, maybe a good thing regardless.

 

I started to have this issue on my 02 RK, only mine was fairly consistant in that it occurred at about 80 mph. It started after 40,000 trouble free miles which makes me think it was probably the isolation mount issue mentioned earlier. I traded the bike for a new one, so not sure what the actual fix was.

 

I think that is what the 2009 frame upgrades were all about.

 

You rented an 09. Don't understand why you would have the problem since the new frame design was "supposed" to eliminate it. Maybe it was related to a different problem. After all it was a rental.

 

The engine/transmission/swingarm assembly is mounted in the frame on two sets of rubber mounts, one at the front of the engine, the other behind the transmission. Rubber by its very nature has a degree of 'give' in it and this is the source of the wobble/rear steer that some owners experience.

Harley partly cures the problem by fitting two stabilizer links, one adjacent to the front mount and another between the heads (on the front head for the latest bikes). Unfortunately they do not provide a stabilizer for the rear mount, but Erik Buell, who invented the system, fitted the extra stabilizer on all his own bikes. So his rubber mount system works extremely well when there are three stabilizers.

The accessory market has jumped on this opportunity and there are at least a dozen different brands out there, all selling their various potients to cure handling ills. They are also available for the latest touring bikes, because while they have a better set-up they still suffer from the missing stabilizer. Dynas have two stabilizers missing!

Personally I have True-Track kits on both my Glide and Dyna and they improve the ride and handling substantially. Along with my Buell I have three bikes each with three stabilizers. It's the only way to travel!

 

Not necessary with new frame '09 and later. Personal preference prior to that.