Had a major case of head shake today

[allisontech]

Well my 2004 finally shook the bars hard enough to get my attention today on the way home from work. It happened as I changed lanes and encountered an uneven section between the two lanes at about 65 mph. Luckily a hand full of throttle lightened the front end enough to regain composure. I have noticed for a while, riding one handed around 45 mph the bars would sometimes oscillate a little, nothing major just a wiggle. Does this sound like a bearing adjustment thing to you guy's? I was going to try the front tire off the ground check I found here on the forum this weekend, from what I read I shouldn't need any parts.
:bang head:
Bill

 

[CaptainKyle]

Well my 2004 finally shook the bars hard enough to get my attention today on the way home from work. It happened as I changed lanes and encountered an uneven section between the two lanes at about 65 mph. Luckily a hand full of throttle lightened the front end enough to regain composure. I have noticed for a while, riding one handed around 45 mph the bars would sometimes oscillate a little, nothing major just a wiggle. Does this sound like a bearing adjustment thing to you guy's? I was going to try the front tire off the ground check I found here on the forum this weekend, from what I read I shouldn't need any parts.
:bang head:
Bill

Just do the boune test thats on the forum. You might just be able to adjust it but there is a possibility you could need bearings.

 

[ouchez]

Get Dingys tool, see the video by Morley from this site as to how to check and then fix head bearings tightness, follow those directions and you should be good to go.

O

 

[KJShover]

Bounce test your front, check your tires for cupping. if everything looks ok take a peek at the rear. Having issues with the swingarm and rear tire being our of whack will also create a steering issue.

 

[allisontech]

Thanks for the help guy's! "I'll do the bounce test tomorrow night".

Bill

 

[allisontech]

I have already bought the new front and rear tires, Captain Kyle has already offered to mount them for me, for a great price. Front tire isn't cupped I just wanted white letters in front to match the worn rear, so I bought 2 new tires. I should have bump tested it while I had it on the center stand for the carb overhaul.

Bill

 

[[email protected]]

My guess would be the bearings are in good shape but need adjusted.

Something weird I noticed about checking bearings for roughness. If you get the front end off the ground and move the bars around it may feel just fine. But, when you remove a lot of weight off the front end, like the wheel, and calipers, and masters, you will move the bars and what felt like good bearings before, may feel "notchy" now.

Not sure why it works like this but it is easier to detect bad bearings in the steering stem with less weight bolted to the forks. I have found this to be true on a few bikes. Typically, this is only with bearings that are marginally bad. If they are really bad you will feel it no matter what.

Not that i think your bearings would be bad, just thought I'd mention this.

 

[gamorg02]

My guess would be the bearings are in good shape but need adjusted.

Something weird I noticed about checking bearings for roughness. If you get the front end off the ground and move the bars around it may feel just fine. But, when you remove a lot of weight off the front end, like the wheel, and calipers, and masters, you will move the bars and what felt like good bearings before, may feel "notchy" now.

Not sure why it works like this but it is easier to detect bad bearings in the steering stem with less weight bolted to the forks. I have found this to be true on a few bikes. Typically, this is only with bearings that are marginally bad. If they are really bad you will feel it no matter what.

Not that i think your bearings would be bad, just thought I'd mention this.

i think it has to do with the momentum of the weight of the setup.

 

[Redbone]

Tire air pressures can cause problems too, just make sure that both front and rear pressures are up to spec.
For example, I run a Metz 880 front @ 34psi and a Shinko rear @ 40psi and have good stability in corners and no wobbles. Yours may be slightly different than mine, but it is what works for me.
If I run lower pressures (33-37psi)on the rear tire it seems to wallow more in corners. I get a slight head shake with air pressures at anything below 30psi on the front. My weight is around 275lbs for reference

 

[RaWarrior]

Probably a loose steering stem. Get a 1 1/16" wrench/socket to loosen the one big nut in the center, and (I think) a 6mm allen key to loosen the clamps. You don't have to totally remove the upper piece, just scoot it up out of the way a bit.

There's special wrenches for those nuts, but I found a big flat screwdriver and a hammer work well. Loosen the top one which serves as a jam nut, then do the bounce check. If it's too loose, gently tap the bottom one tighter until the bars don't bounce off the stops anymore.

 

[allisontech]

Well your ideas were right on target, I checked the bike tonight and it failed the bump test.
Going by Morley's video it took about a 1/8" or less adjustment to get the desired results. A test drive tomorrow to work will decide the results. Getting the new tires mounted, is next on my agenda. Thanks for the help guys, this forum is the best!

 

[allisontech]

Life is good! One handed riding no longer creates a shimmy of the bars, And no sign of high speed wobble during transitioning uneven pavement. Thanks for the info guy's, This forum is awesome!

Bill

 

[Garbilizon]

:clapping:

Can you post a link to the video please?

 

[Redbone]

:clapping:

Can you post a link to the video please?

Here ya go!
http://www.youtube.com/watch?v=OW-CmACI5xQ

 

[allisontech]

Thanks for posting it Redbone!

Bill

 

[allisontech]

Now that I had the new tires mounted yesterday it seems the front tire was also a factor,contributing to the wandering. "Even with the wobbles gone, the bike seemed to follow every imperfection in the road, I thought it may just be a handling characteristic of the bike, since it has always been that way" Well with the new Qualifiers mounted the bike is now what I would call normal" The front tire wear honestly didn't seem that bad,I did notice the tire was no longer rounded as much as the new tire,the center was raised 1/16th from the rounded sides,but no cupping was evident.

Anyway life is good, "scrubbing the tires in, is next on my agenda"
Thanks again for the help!

 

[SpecOps13]

The wander, if it should pop up means you need to tweak the adjustment a tiny bit looser. If the bearings are a little too tight they can induce a wander. I had to back my adjustment off just a slight amount when we did the adjustment at one of the Tech Days at Kyle's..


Luckily, My 89 has had all the fork work done to perfection. No wander and well over 100 produces no wobble ...

 

[jbretthorton]

What Dave said,
Mine was doing the same thing. Just had to loosen just a tad to stop to wander.

 

[allisontech]

Should I still mess with it now that the new front seems to have corrected it? It seems there was also allot of road noise being caused by the old front tire. The road noise seems quieter now at 60 mph or so with the new front tire.

Bill

 

[[email protected]]

If you're on smooth pavement and the bike will track easily in a straight line without to the need for you to correct it and it doesn't have headshake anymore then I would say you're good to go.