Steering trouble

[mandosi]

Any advice for a consistent wobble at 30 to 40 mph...after 40 it smooths out...not tank slapping wobble but increasingly noticeable...

[Jon_P]

i have not idea, i will follow this thread to learn with you for sure.

[Bob_Roller]

Have you done anything to the front end lately? Check all fasteners for tightness, and check to see if you have lost balance weights on the front rim. A quick check of tire pressure wouldn't hurt either.

[thrang]

tyre tread depth is worth a look..

[Justin B.]

If your tire is balanced, wheel bearings are not sloppy, and steering head is greased and adjusted properly every other time I have had a shake at this speed range has been due to tires - Metzlers in all cases with plenty of tread left.

Do the "shake" test on the front bearings (easiest), check balance (second easiest), then service head bearings.  If this is a new bike to you it would probably be a good idea to do all of this stuff anyway as it is in a major 10k service which should always be done when you get a new bike so you have a maintenance baseline to work from.  Do a search as I think I posted a checklist a while back...

[Semper Gumby]

+1 on Justin B.  Where to begin...

Wheel bearings (front and rear),  steering bearing, swing arm bearings.  Check 'em.  After that is done get the wheels spin balanced.  How old are the tires?  Are they dryrotted?

I would add - Has this bike ever been crashed?  Could be bent frame?

Good luck.

[mjbickford]

i had a similar thing symptom develop recently.  Between 40, and 35 when decelerating only.  It has gone away since replacing the overly worn rear tire.  It could be the tire pressure, or tread depth.  Check the easy things first.

Its amazing how different the bike feels with a new rear tire.  the front is still useable, but i went from a 120/90 lasertec with steel belting showing, to a 4.00/90.  Now the bike seems to sit higher and not feel as mushy.  I had no idea a rear tire could affect handleing so much.  Once i get new shocks on her, ill be set!

[ciciban]

Hi!

I also had problem with wobble at low speed. I replaced tyres with new Michelin Macadam and the wobble disappiered.

[mandosi]

Ok...brand new Metzlers front and rear...new wheel bearings in front. The steering head was adjusted but I'm thinking it may need another. I believe i've got a good guy helping me with this bike...all in my area (RI) say he is the only guy to have work on an old BMW. It feels like it's in the wheel less then up at the head...running 32lbs air in the front and 34 rear...I know the manual says 28lbs but that's been changed I'm told. I've inspected the wheel about 20 times but I'll look again to see if there is a missing weight. There is some runout in the wheel but it appears minor...could even the slightest runout cause this? I'll check the air pressure front and rear...and another tweek to the steering head may help.

[mjbickford]

could even the slightest runout cause this?

Yes!  Clymer says more than 2mm, check the wheel bearings, if good buy a new wheel.

[NC Steve]

I run 35 and 35 lbs., front and rear, and have had similar handling problems if the front is less than about 32 lbs.
In fact, I can very quickly feel when the pressure is low, even by a couple lbs.
Just my  [smiley=2cents.gif]...

[suecanada]

I had that wobble/weave at that speed too and I changed my tires to new ones (all Metzlers) and that pretty well fixed it but don't eliminate steering head greasing which seems to have eliminated all traces of wobble.  When my bike wobbled the worst was with loaded saddlebags and watch that you don't load the bags UNEVENLY!..that'll really accentuated the wobble.  I looked at tire pressures for ever and they never were the reason for the wobble.

[mandosi]

Well you guy have steered me in the right direction(forgive the pun!) I checked the air pressure again and found 28 lbs in the front and 30 in the rear. That's a 4 lb difference from where it was...I brought the front up to 32 and the rear to 34 and the wobble is essentially gone! I'm surprised it's that sensitive but so I've learned something else...no back to that starting problem...

[Justin B.]

Interesdting, when my front Macadam gets under about 30 psi it doesn't wobble but really starts tracking the rain grooves.  I love EASY solutions!