2001 FXDX with 6,000 miles.

Anything over 85mph my bike starts to rock side to side really bad. Not in the bars like I'm trying to turn them, but the entire bike back and forth as if I was trying to lean it over side to side really fast. NOT FUN trying to blast down the highway.

I know people get wobbles in corners because the swingarm is mounted to the trans, but mine is solid in the corners.



If it helps: I'm about 160lbs, bike is all stock besides bars and HD 1/4 fairing. ....stock mag wheels, tires are dunlop k591 with less than 1500 miles, new wheel bearings and wheels balanced when the new rubber was put on. The bike is new to me but seems to handle and ride fine except for this.

 

try doing an alignment.....I've pegged my speedo and never wobbled a bit

 

One thing that will also cause this is if the forks have been dropped in the tree mounts.
(Lower trees = better cornering but high speed wobble.)
I've also seen wind screens magnify this effect, which may be what you are having.
You can test it by taking the wind screen off and doing the same run.
So...Tire pressures, front and rear suspension properly adjusted.

 

I have the same issue, only mine is at lower speed (60 mph while in 5th or 6th). I've been told, tire pressure, loose spokes, fall away sumthin or other. I've tried the ones within my limitations. Haven't rode it,waiting to go back to HD (SH**). Be careful bruh.