Good evening!

I been having an interesting predicament that i always thought was only subjective to the super bugs. I have front end shimmy shake on my 69 beam front baja.


At about 65kph, i get a feeling in the steering wheel like a wheel out of balance, but it grows harder and starts shaking the car. It grows at the same speed, and i can snap it out of it if i turn left or right hard and back at the same speed, or hit the brakes quick (Without loosing much speed) and it goes back to norm. But a few mins later it can come back or sometimes never comes back till the next drive.

I can stick my head out the window when its doing this and can see the front wheel (only can see on the drivers side) shake like crazy, but when i snap it out of this vibration craze the wheels roll true and fine.

My suspicion! Is that the urethane torsion bar bushes allow for it to shake, and like any resonance/natural frequency the displacement just builds up and goes crazy. I don't have the stock roller bearings in the torsion tubes any more.


What do you guys rekon?

has anyone else had this on a beam front bug?

Some days it never happens, others it comes every 5 minutes. :S

Thanks for reading,
Christopher.

Check all your tie rod ends , wheel alignment etc .
As a basic check on your wheel alignment you want the front of your tyres to be approx 3mm closer together than the rear of your front tyres and thas sitting on the ground at ride height .
Hows your steering damper ????
And lastly your beam rake may be a bit out due to your suspension settings

Awesome! Thanks Andrew i'll have to have a sticky beak at all of those. The wheel alignment was done approximately last december and the tie rods were new german ones that have seen the road for about 12 months. The steering does like to drift to the right so it could be out of whack given the drives i have had. i was told that weight distribution in the car (like driver in and no passenger, weight on right on drivers side) causes the car to pull in that direction with that side squatting a little, does this sound right? This was a generic 'non-vw specialised' steering mob's opinion so took it with a grain of salt.

The steering damper was new and only saw the road for 12 months, BUT! it is brazilian, soo could be the culprit. However it seems any new vw bit seems to be a dud occasionally. I'll check on Tuesday.

Much appreciated mate

also check to make sure you check for wheel bearing play

Don't forget to have your tyres balanced. It may be that simple!
Dave

Quote:

Originally posted by bajachris88 Awesome! Thanks Andrew i'll have to have a sticky beak at all of those. The wheel alignment was done approximately last december and the tie rods were new german ones that have seen the road for about 12 months. The steering does like to drift to the right so it could be out of whack given the drives i have had. i was told that weight distribution in the car (like driver in and no passenger, weight on right on drivers side) causes the car to pull in that direction with that side squatting a little, does this sound right? This was a generic 'non-vw specialised' steering mob's opinion so took it with a grain of salt. The steering damper was new and only saw the road for 12 months, BUT! it is brazilian, soo could be the culprit. However it seems any new vw bit seems to be a dud occasionally. I'll check on Tuesday. Much appreciated mate

Chris, I've had the same issues, maybe it's the Thing stub axles. My front wheels aren't perfectly true and I feel that's the catalyst for the shimmy. I posted the day before you started this thread mentioning the same with my baja. After adjusting castor and toe I have improved it heaps.

http://forums.aussieveedubbers.com/viewtopic.php?tid=69105&page=17#pid920577 

Incorrect castor? Is your beam wound up at all?

While you are checking the front end, make sure the frame head is not cracked, or detached from the frame.

I just repaired a car with the same complaint.
It had early (6 Volt) stub axles and someone had replaced the right hand wheel bearings with late (12 volt) bearings.
The inner diameter of the inner bearing is about 2 mm less on the early ones.
No wonder it was wobbly!

thanks for all your support guys, i believe i have found the cause of the problem.

I bought a new steering damper knowing that the original i put on was a brazilian. i now have a BOGE german one. but upon disassembly, the old steering damper was fine. Anyways, now have a spare.

I don't have bearings in my front beam, i have urethane bushes. the passenger side bottom torsion tube has massive amount of moment, allowing the whole wheel to move significantly. Its moving in the urethane support which tells me the urthane must be cactus. Because of the movment, the torsion arm is probably bouncing between the urethane sides like a trampoline.

i have an original beam at home with the original needle bearings, i think i will just stick with needle bearings. no weekend play for Chris due to time contraints, but it is nice knowing the problem location and thus will be able to implement the solution. I was thinking of swapping beams anyways so i could put bigger front tyres on while keeping the same height (curing the whacky wheels racer look).

it was a funny one, because it never shimmyed like this when i first got it registered which was 12 months ago with all the thing suspension components fitted.

Good to find the problem Chris

I don't like urethane anything as they cannot twist like rubber
they are too hard and not flexible..
yet not good enough to replace needle rollers..

rear torsion bar bushes too..

Rubber Only....

OK on the Brasillian steering damper..

Many things are now Brasillian... hopefully GOOD brasillian
and many parts were made by the same original company but in Brasil.. not Germany

cheers

LEE

Ahhh. The old urethane beam bush saga rears it's ugly head again!
Methinks a new thread is in order!

oH! haha, just saw this after posting in your thread lol.

I'm off to go back to OEM style needle bearings.

Recently the Manx SR has had attacks of the death wobbles, at random times when I accelerate at maximum and always when I accelerated at maximum from a certain set of lights.

I'm still a bit of a hoon.

It comes on at about 60km/h and I have to slow to about 50km/h to get rid of it. It never happens if I accelerated slowly right up to 100km/h on the freeway.

I checked the front end to find that the bolts on the tie rod ends had not been tightened after a recent front end alignment. Everything else was O.K.

This problem never happened before the front end alignment.

I cursed and tightened the bolts. I can't see how this would affect the front end, but I haven't driven the car since then, so I can't report on any improvement.

The front end is a standard 1968 ball joint with 4 year old ball joints and very good bearings and surfaces in the torsion bar tubes.

Have you been greasing the bushes Chris?

Cause they need to be lubricated or they will wear out.


Smiley

How did you go with this, Chris?
I am interested what you have found with this!

Quote:

Originally posted by Smiley Have you been greasing the bushes Chris? Cause they need to be lubricated or they will wear out. Smiley

You also need to make sure that you a lubricating with the right lube.
Some lubricants have a chemical reaction with the urethane and cause it to break down and go soft. I was reading something about this on The Samba, but can not remember what lube they said to use.
Perhaps this is was happened to your bushes?

To check the bearings on you other beam fit one of the trailing arms in with nor torsion bars and check to see that it has no play or movement back or forward inside the tubes.



Smiley