violent shaking handlebar !

[jsamaniego]

Hi everybody!
My 04 used GS500 has a problem I've never encountered before: if I leave the handlebar alone it begins shaking violently. It seems that the shaking keeps increasing in angle (of course I stop it immediately),.
I've been using a TU250 for 26000 kms and I could ride it with my hands in my pockets... now I can't leave the handle bar alone! :x
Does this hint to a fork problem? I bought it used with 550 kms and the previous owner did not have a crash...she says.
This is not normal ain't?

Since it is still under guarantee, I'd like any help on how to present the problem to the Suzuki dealer...
TIA !
from Florence, Italy :

[GSRider]

Your front wheel may not be in alignment or balanced correctly. Take the bike back and have them re-balance it for you.

Do you see any weights on the rim?

[jsamaniego]

Yes, it has the weights. Someone tells me it has to do with the fact that I've added a box on the back.  The box is empty,though..
Could it be? :dunno:
Note that the shaking is NOT vertical.. The handle bar shakes sideways, like zig-zagging violently...

[GSRider]

Well, the issue then could very well be that the front doesn't have enough weight on it. I used to get bad head shakes when I was going a little fast, but it all stopped when I started leaning on the bars more, and shifting my weight more forward.

Then I got my cafe racer bars, and I no longer have to think about it, more weight was instantly put on the front because of the riding position.

Maybe strap a 40 lb weight on your bars? :lol:

[Kerry]

Benvenuto Javier!  Come stai?

The first thing I would check is the air pressure in the tires, especially the front tire.

FRONT: 33 psi (2.25 bar)
REAR: solo = 36 psi (2.50 bar), w/passenger = 41 psi (2.80 bar)[/list:u]If that checks out, let me know and I can send some info about

steering head bearing freeplay.

Viva La Fiorentina!

[mp183]

Check the pressure first like Kerry says.
Put the bike on the centerstand and have someone sit on the back so the front wheel goes off the ground and rotate it as quickly as you can and see to make sure it's not warped or otherwise damaged.  If you don't have someone to sit on the back you can stick something under the engine to raise the front wheel.

[jsamaniego]

Thank you all guys for such overwhelming responses!:thumb:
I'll be away for 2 weeks (I'll miss my GS) and I will not be able neither to follow your recommendations nor to respond, but I'll keep you posted as soon as I get back.
In any case, since the bike is new (Jan 2004) I do not expect major wheel misalignment problems.. I'll let you know.
BTW, any trick to see on the rear mirrors while riding at 60mph and actually SEE something (not blurred?)

p.s. La Fiorentina is back in first division!

[Kerry]

any trick to see on the rear mirrors while riding at 60mph and actually SEE something (not blurred?)

Sometimes the best you can do is simultaneously pull the clutch in & roll off the throttle ... take a good look at the now-clear mirror view ... and then return the clutch and throttle to their former positions.

I haven't seen Firenze since I lived there for a few months in mid-1983.  One of these years ... "I shall return."  

[Sportbilly]

My ZR-7 was always stable as a rock, till I put the bags on the back, I think it's more of a harmonic frequency thing, as you change the mass of the pendulum(the bike) the frequency of the oscillation changes.   If it happens to make it so the oscillation is sypathetic with whatever is exciting it, then you get positive reinforcement and thus, the head-shakes.

Having said that mine went away again, when I put the screen on.  And my GS never behaved badly at all, with any sort of luggage on the back.

[Richard UK]

Had a similar problem once with a little Honda.  Turned out the side walls of the front tyre had failed and the tyre was coming apart from the inside out.  New tyre (hey! sorry guys, I mean tire   ) and the problem went away.

[slotcar]

My shakes and wobbles went away when I did the following things: Loosened all front end bolts except the top  trees and bounced the front wheel into a wall or  solid post and tighten the bolts again; added bar weights; Progressive fork springs and 15 wt fork oil; new Metzler Sportec I tires. Rides hands off, straight and smooth.