I recently installed a Sputhe Stabilizer (front and rear) to my 07 street bob to get rid of the dyna wobble. Instead of fixing it though, the wobble has become significantly worse. I have a terrifying wobble at straight speeds over 70 (more to the left than right) and a low speed deceleration wobble (20 or less) that actually shakes the handlebars side to side. Cornering wobble is scary and FAR more noticeable than before.

Before i pull this thing off, any ideas? I tightened up the fallout, spokes are tight (running dyna beads), tire pressure is right on, and motor mounts are in good shape (10k miles and inspected). I also unbolted the entire stabilizer thinking it may be stressed and i was able to hand tighten the bolts. Brought it to a shop too and they had no ideas. Any advice? Please and thanks!

 

Kind of an unusual problem. Just by intuition, I wonder if by tightening the fall away you have created a problem. Check with Sputhe, they might have a fall away spec that is required forr the stabilizers to function properly. Hope this helps.

 

I only tightened the fallout after the problem started so that shouldn't be it. Im stumped! It isn't the shocks either had no problems like this before and have the same Works 14" in the back

 

The only other thing I can think of is wheel alignment front to rear. Could the installation have affected the swing arm alignment?
An outside shot is a bad wobble at various speeds I have experienced when a front wheel bearing wore out. That's clutching at straws!
Wish I could give you a more authorative answer.
Good luck, If I think of any more possibilities, will post.

 

I would suggest looking at the wheel bearings also.

 

how closely have you checked your shocks

14" is pretty tall, if you have a problem the taller shock will multiply it

i would also take the front wheel off and see if forks are equal, maybe one leaked out the fluid.

i would also put stock lenght shocks back on and see if the problem is better or worse

 

I will check the wheel bearings. Anybody else have any ideas what could cause a high speed wobble and a low speed side to side handlebar shake?

 

Take the Spluthe stuff off and start over with an alignment first. Jack your bike up to get it off the ground loosen the motor mounts and the top stableizer start it up and let it settle into place and tighten everything back up and see how it goes from there. I don't have any of those aftermarket stabilizer gadgets. Last night on my way home from work I pegged my speedo (120+) and my bike went straight as an arrow. I took my hands off the bars and no wobble or shake at all.If your bike shakes and wobbles as bad as you say start at the beginning. Don't just throw **** at it and expect it to go away. Get to the root cause of the problem.

 

I've not worked on a later model dyna.. Own a 2000 FXDX.. Anyway I've not had much luck with the Sputhe stabilizer either.. When I was chasing issues, the only thing the Sputhe did was change the frequency of the wobble.. I suspect that it is due to the rear stabilizer.. There is just too much flex in the design of the rear stabilizer.. It doesn't surprise me that it could make things worse..

Not sure what the stock shock lenght (12-13 in?) but jacking up the rear will decrease trail which tends to decrease stability.. Seems like that and the Sputhe stabilizer has created an unstable condition..

Now you mention a low speed side to side also.. If it is more like a shake, tire pressure is usually the cause followed by worn tires.. What are the condition of the tires? Have you tried adding 4-6 psi to the tires?? Replace them if suspect..

With longer rear shocks, have you checked sag on the front end.. You probably want it about 1 1/4 inches.. Too much sag decreases trail even more.. Works shocks are some of the best around but they can bring out weaknesses in other parts of the chassis.

Alignment is very important. I generally align the rear wheel by looking at how the belt tracks then see how well the rear points to the towards the front.. Also does the rear wheel run vertical with the frame and front wheel? Getting that straight helps a bunch..

Are there any worn parts.. Mileage? The rear swing-arms get loose, steering bearing loose, The motor mounts tear. Wheel bearings. Spokes.. FWIW I'm not to hot of the stock rims.. They actually flex a bit.. Alloy hoops work a bunch better.

 

This is why I have always said you need to find the real cause of a problem before you start adding band-aids to hide the problem.
The Dyna wobble is not an inherent problem with all Dynas, it is an idication YOU have a problem with your bike.