Front wheel wobble

[waricle]

I noticed that if I take both hands off the bars the front develops a wobble.

It's not severe or difficult to correct and I would like to know the possible causes.

Tyres are about 1/2 to 2/3 worn and suspension is set firm.

Any suggestions??

[rktmanfj]

Don't take both hands off the bars...

[terryk]

This  "wobble"condition can be caused by a fairly large number of issues including but not limited to, cupped tires, tire imbalance, uneven fork spring wear or a bad fork spring, front and rear tire misalingment or even a tweaked fork or triple clamp, and on and on it goes.

[waricle]

any other other suggestions?

[Flynt]

any other other suggestions?

Check for bent wheel, solid bearings, brake rotor warp, cupped tire, etc...  Any decent shop should be able to ride it and tell you what's up.  Odds are tire cupping...  just hold onto the bars as was suggested earlier.

Frank

[E Double]

What speed does it happen at?  Or is it occurring at a range of speeds?

If the steering head bearings are in good shape dollars for doughnuts your front tire is cupped.

FJ's tend to be hard on front tires, what with their weight, skinny front forks and typically running bias ply tires.  But tires will cup anyway on a light bike with a stiff fork, because of the forces acting on the tire under braking and turning.

Proper tire pressure helps keep cupping at bay for longer;  I typically run 37 psi in my front, and it has only started showing signs of cupping at around 12,500 miles.  But I run radials (Avon Azarro ST front and rear) and they tend to resist cupping for longer vs the bias plys I've run.  This is an awesome resource about tire cupping;

http://w6rec.com/duane/bmw/cupping/index.htm

[SlowOldGuy]

Every time I've had that problem, a new front tire fixed it.

DavidR.

[waricle]

Thank you all for the replies,
I will check the obvious faults first but it looks like I may need a new front tyre...

[FJTillDeath]

Tyres are about 1/2 to 2/3 worn and suspension is set firm.

Any suggestions??

1 - as others have stated keep your hands on this is not a "look mom no hands "

As for the tire being so worn I would definitely get a new 1. In South Africa if I had to get pulled over with a tire as worn as you describe Id have to pay quite a fine

[Adam FJ]

Are you running a standard rear Shock ?

I had the exact same symptoms and after checking and changing a shed load of bits found it to be a rear shock that had no damping.

Adam.

[Dazza57]

Love your BMW cupping bit E Double, beautiful. Must try it some time, good for some laughs. Agree with the others, why take both hands off the bars ?  Got me stumped
2/3 worn front tyre, IMHO way past the "use by" date

[andyb]

Why not take both hands off the bars?  If everything's working properly it's okay, guys, sheesh!

If it happens at a given speed and gets worse at higher speeds (eventually it'll show up even with your hands on the bars), it's unquestionably the tire.

If it persists with a newer tire, most likely culprit is the head bearings.  Both of these are assuming you're not doing really strange things with the chassis geometry.