Hello to all,

I have a serious fork wobble on my '97 Road King. It will shudder at 100 MPH on the straight (sometimes), will wobble on a pressed lane change at highway speeds (sometimes), and is absolutely unsafe on tight curves at 45+ MPH. The bike will sit until this resolved.

Leaning or pressing into the curve seems to make it worse. There is no holding the bars from wobbling, and it feels the front end is going to fold like a suitcase. Even more scary, is the bike does not want to respond to a lean or press in a curve - just wobble more.

I put it on a jack. The forks have almost no resistance, but the bearings are not loose - that is, there is no play. No play in the wheel bearings either. No cupping of the tire.

I expect it is the rear of the bike (perhaps a swingarm?). I will remove the bags and inspect it, but suggestions are appreciated.

Thanks,
-John

 

My '07 Road King acted like that a while back, was almost like trying to ride a sponge, I kept checking the front and never found anything. Finally found out the rear spokes were loose. Took those wheels off and put on cast wheels, no more wobble for me.
You may want to post this in the touring board too. Couldn't hurt.

 

Good idea, maybe it will save a life. Spokes were suggested by a friend and will be checked. Damn violent and real scary.

Thanks,
-J

 

100 mph wobble! my nuts start shrinking @ 100 mph on a big bike, you must have some cahuna's The swingarm is known to crack on the earlier Roadkings, sounds like it is flexing or possible swingarm bushing problem but have had some friends that had the spokes loosen up also as mentioned above. The stock swingarm bushings are liquid filled and might have softened up, they have a history of causing the uneasy feeling on uneven surfaces and while accellerating out of curves and also check the rear axle bolt for moving around. Good luck and please keep us informed, expecially me if the death wobble visits my bike.

 

Some other things to check would be, fork air pressure, tire balance, when was the fork oil last changed ? any leaks at the fork tubes?. The forks act just like the shocks on your car. If you're ever seen a car with one bad shock, that wheel will bounce like a basketball while the other looks normal. On a bike that might also be a broken or weak fork spring. Just throwing darts.,,

 

When the last time the wheel bearings were serviced?

 

One of the easiest things to do would be tighten the Steering Head Bolt a hair. I had a wobble at around 45mph if I took my hands off the bars, the Steering head felt alright but I tightened it about a 1/4 turn and the wobble disappeared and that was over a year ago, still no problem. Could be something else but why not try that first.

 

Appreciate the input.

It seems we are all in agreement on possible causes. The bike is down and will be until I can tear it down (just moved and am behind).

BTW, the wobble is not wheel hop, but an uncontrolable side-to-side fork wobble (the handlebars move left and right several times a a second) - very scary.

I'll post when I know.

Thanks,
-John

 

John seeing as the bike is down you may consider starting with the wheel bearings and working your way along with all the suggestions seeing as not a one of the suggestions are all in par with regular maintenance. Just a thought as you say the handle bar goes left to right wobble, have you considered a bad tire?

 

Sounds as if your bike needs a health check from stem to stern, taking in all the usual suspects as you go. There are things to improve handling at those speeds, but they can only be effective when everything else is spot on!

Very often front end problems have their origins at the rear, but the front is probably the best place to start. Best of luck and we are looking over your shoulder!