This is probably a silly question to the more experienced riders, but here goes:

1986 FXRS. As far as I know, stock suspension, Dunlop/ HD tyres (for your, Graham!). When riding straight and level everything seems great. When going around a corner at higher speeds (60MPH+) and hit a "dip" in the corner, the bike starts bobbing and swerving. I checked the air pressure in the tyres and it the problem is better with correct pressure but is still there at higher speeds. I have completely rebuilt the front forks and changed the fluid (HD Fork oil). So I'm wondering if the swing arm bushings are weak, the rear shocks are weak, or is this just nature of the beast? It has never been uncontrollable, but it won't allow me to really "lay it over" for fear the road might have a bump (welcome to Iowa roads!). It is worse with a "dip" than a "bump."

Thanks guys for your knowledge and your willingness to share!

 

If your bike is still stock you probably have the original cleve block swingarm bushings. They are probably knackered (that is a technical expression!) and they have a little 'give' in them even when new. You could consider replacing them with solid bushings such as StaBo or those from HDF sponsor Motorcycle Metal. Alternatively you could go the whole hog and install a True-Track Trackula kit, like I have on my 1990 FLHS.

This includes bronze bushings, plus an additional stabilizer, like all Buells have. Your bike currently has two stabilizer links, one between the heads, the other in front of the engine. The TT one goes under the gearbox to prevent lateral movement in the rear engine rubber mounts and tightens things up considerably. A Buell it ain't, but it will be much closer! TT is also a HDF sponsor.

Then there is your shocks. If they are old they also could be knackered! And you could also try Avon Venom tyres, just to finish things off.

If you haven't found out yet, we are very good here at spending your money!

 

You didn't mention if it was the rear of your bike that was 'washing out' in the curves. As mentioned, check your swingarm for worn nylon spacers, and weeping gel bushings. Dunlop 401's are a little hard....

Do you have a fork brace?

Worn shocks, check mounting bolts, torque to spec.

Steering head been checked? A lot of riders set the steering head pre-load a little heavier than the factory does with good results.

The FXR's are easy to figure out.....just takes some time.....good luck

 

I've never done a thing to the steering head- have no idea what previous owners did. It seems to be the rear of the bike that washes out.

I forgot to mention the bike has 40K miles on it-

Although I'm not a motorcycle mechanic, my first inclination is either swing arm bushings or rear shocks, just wondering which ones to try first.

 

Start with the foundations! As an example, putting a comfy seat on a bike if the shocks are shot ain't going to give much comfort, as that is the wrong place to start. So Your suggestion of bushings is right. then work outwards, so to speak, sorting things as you go. If the bushings are shot and you 'fix' them with a True-Track kit you will sort that problem and significantly improve the bike at the same time.

You will then be in a better position to decide if your shocks are OK. The cherry on the cake is good tyres!