Weebles wobble

For as long as I have had my motorcycle I have been running at lower speeds less than 50 miles an hour now that I've got things tune to where I think everything is perfect I have gone past 60 miles an hour and up to 70 but I get a really bad wobble can anybody give me an idea of what is causing this

 

Could be tires, or loose head stem bolt. Possible front wheel bearing.

 

Could be any or all of ; wrong pressure in tyres, out of balance wheels, wheel bearings worn, loose / worn steering head bearings, loose / worn swing arm bearings, bad shockers, uneven amount of oil in forks, loose axle nuts. Bad wobbles should be fixed quick, it can lead a horizontal situation.

 

Tire pressure is good tire balance is on point. I believe my wheel bearings are in good shape I'm not getting any play other than just a mild wiggle I cannot get any play out of my Forks whenever I pull on my front tire so I believe my bearings at my handlebars are good I might need to look into the swing arm bearing and the shocks and the oil in my Forks

 

I am having the same issue with one of my bikes. I get a wiggle when let off the gas and I am not holding the handle bars thight. Like with one hand to rest. I noticed that if I sit on the bike and giggle the handle bars, I see some side play on the front wheel/axle. I plan on changing the bearings.

 

put bike on centerstand and try to wiggle back tire to see if bearings are shot. then the same thing for the front wheel.
then try turning the bars left and right see if you feel a bump when going past center

 

And uneven wear or cupping of front tire will send bike tankslapping off the road, Even if everything else is good. You should have NO wiggle in front forks.
Bike on Center stand , jack or blocks of wood to suspend front wheel there should be no rocking of the forks front to back and front fork will swing smoothly left and right with no detent feel at all. If it wants to stop in the middle I call it "auto steer" = bad head bearings

 

Another thing to try pull caliper off mount put bike on center stand , block it up so front wheel is off the ground, spin front tire if it spins in circliar pattern this will rule out an out of balance wheel if it moves in an oblong pattern then you might have an unbalanced Wheel or bad wheel bearings. If your bearings are original it might be time to replace. One thing if you pull calipers you do not have to pull the brake lines.

 

Believing that the steering stem beraings are good is not the same as knowing that they are good. Pull the front end and inspect. You will probably find that the head bearings need lubricated at a minumum. There's more than an even chance that the races are notched as well.

Going through the whole bike means going through the whole bike.

 

Thanks guys for all of the very knowledgeable advice. I think that the answer is in one these replies . k-moe is right go through the whole bike.

 

Ditto on the whole bike thing, but have you taken the front fender off for any reason or checked that the bolts are tight? I meant to post a video when I rebuilt mine but the amount of twist you can give to the forks without the front fender is amazing. I will strongly argue anytime someone tells me it's not a structural piece. After that, I'd be checking steering stem bearings. Death wobble sucks.

 

FWIW, if you decide to look into replacing the steering bearing I just did them with the All Balls tapered bearings. In fact I was beginning to put it back together this evening. Hogfiddles has a nice walk-thru with pictures on checking fork alignment.

http://www.xjbikes.com/forums/threads/dropped-bike-need-help.97887/

 

More than likely the steering neck bearings. I it all apart last night because of similar symptoms and found deep groves worn into the races.

 

I agree with nearly all the above - but I'm not convinced differing oil levels (in forks) will cause a wobble. They are braced and work as a pair as far as I know. If one was empty and the other correct level they would be softer and might bottom out but that's all (do feel free to correct me on this if you know better!)

Cheers

 

I did noticed that when i ride by myself 190 lbs... I CANT LIE TO YOU GUYS, 200 lbs. it will wobble, if i have my daughter on behind me 110 lbs i get a very slight wobble, if i have my wife on 122.6325 lbs i don"t get a wobble at all, and no i can"t take her with me all the time. That's not fixing the problem. Only creating another one. What do you think the weight change is doing to relieve the problem ?

 

That makes me suspect the swingarm bearings. Are you adjusting the shock preload when you have a passenger?

 

You are correct. There are some fork systems where one side is just the damper, and the other is just the spring.

 

I have it on the third point, the one next to the strongest. I'll try the strongest when i get home.

 

The dial on the damper, to me it seems like it doesn't do anything, you can spin it around and around. It does click at every number tho.

 

It's supposed to spin around and around. There is not final stop; you can go from 5 to 1, by design.
That upper dial controls the damping (you'll only notice the effect while riding).
The collar at the base of the spring is what changes the preload.

 

It might be worth a shot to loosen and retorque the adjuster stub under the cap for the swingarm pivots. As the bearings wear, tolerances start growing which may have caused some side to side play in the swing arm.

 

Can you explain what damping is doing for me ?

 

If the swingarm bearings are worn enough to need re-adjustment, they should be pulled for cleaning, inspection, and re-packing or replacement as warranted.

Truhfully, they should be pulled anyway. It's likely never been done, and that grease is old.

 

I agree, she only has 19,000 on her but that makes sense its 35 yrs old and i don't know if there was a two ton tessie that rode her before me.

 

So my understanding is, that the numbered dial on the top of the forks and the top of the shocks is whatever number it is on that is the damping, it is ? The damping , is it like a different size hole to allow liquid or air to pass per number ?

 

Yes, and yes. The shocks are oil filled.

 

good to know, i did not know that but was thinking it was. could be my problem. Thank you everyone. I've got this thread to go through and try each one to see what solves the problem, again, thank you for all your idea's and knowledge. I love xj'forever and the members.

 

You may be overlooking something simple. Is the wobble more like a weave?
Next time you feel it try relaxing your grip on the bars and grip the tank with your knees.
The natural tendency for most is to grip the bars even tighter which amplifies the weave.

I'm suggesting this because you say its better with more weight (dampening the weave) on the bike.

 

I'm pretty sure its a wobble, it goes back and forth real fast, like you see in the videos just before the crash, but mine only moves about an inch or two back and forth. I back off the gas before it gets worse. I could be griping too tight, it is fast and its been 35 years sense iv'e gone that fast on a bike.

 

Hmm, that does sound like something with the bike, however another easy thing you might try is altering your seating position, moving forward/back in the saddle and see if it has any effect.

 

I will give that a shot, i prefer a simple fix over a complicated fix any day thanks.

 

Warning Will Robinson and Door Dude... yeah I've seen that first hand on a mates borrowed bike, it was 'kn horrible and then I went for a slide and needed stitches. Tank slapper is the term. I recommend fix the problem.

 

Well over the weekend i started checked all the things suggested here on this thread. I found 1 fork that was about a tenth of 1 oz lower and my rear shocks 1 damping was set on 3 the other on 5. I let out 2 lbs of air in the front tire. Took her out for a ride loose grip and knees tight on the tank then bam... blew my toupee off. I didn't know she could hit 80 so fast. NO WOBBLE. Thanks guys.