Trucho-951

Well my car still shimmys, but it's not really detectable by others, I just happen to know it's there, and it is annoying to me.

billthe3

Just be glad our cars like to shimmy dance and not grind with other cars.

chrisj944

I was having the same problem until yesterday when I got the tyres rebalanced at a different garage to usual for the 3rd time and bang, problem solved!!!

Maybe you should try getting the wheels balanced at a different shop. Could be that there equipment is out of callibration or something maybe... Good luck though. shame that such sweet cars seem to be plagued by this stupid little issue

PeteL

Tire balance and pressure were the main culprits on my car.
I went the route of new bearings, control arm, etc. The shimmy would always return...usually would be resolved with air pressure. Finally one of my old (very old) tires disintegrated. New tires, good balance, good pressure...no shimmy! Big smile!

Rip It

Mine did this with worn out struts, went away after I installed new koni inserts.

Mike C.

You might look aroundfor a garage that can do on-the-car wheel balancing. I happen to have an old strobe light rig and can spin the tires up to well over 120 mph (the early cars have the speedo cable going to the left frontwheel). I'm able to tune in the balance much finer than your typical off-car computer tire balancer.... It can even be done by feel but that takes a bit longer since weight placement is more trial & error. You do see these balancers come up on ebay every once in a while..

Yabo

Well, feeling a little silly but I think it was a couple things.

I switched wheels front to back this morning and shake seems to be gone (one 15 min drive). Might be speaking too soon as sometimes it was hit or miss, but I think it must have been wheel balance.

I think it was also alignment though because it would shake before when I have switched wheels front to back, because I switched them every autocross or two to keep wear as even as possible.

I'll let everyone know if it comes back, but looks like its either bent wheel or out of balance wheel. Have to at least replace the tires on the back now anyway, and you can't really feel the vibration when it's on the back.

I also have to see what happens when I put the right air pressures in because I haven't adjusted them yet and right now its about 33 in the front and 30 in the rear since I switched front to back.

Thanks for the help.

hpservertech

Have had this on many cars. Majority of the time it was an unbalanced wheel. One time it was a shim though. Dont think our cars use shims, correct me if I'm wrong here.

If you moved them from front to back you should feel the back shake some eventually.

jsaindc

My S2 did this and found a wheel was slightly bent. I could hardly tell visually but the shop spun it and you could tell. Bought a used wheel and it almost went away...almost.

safulop

Bumping,

is there a more current verdict on this? I have "the shimmy" in my 1985 944 that I want to sell, and I need to explain it to potential buyers. I've noticed that it depends quite a lot on tires, getting worse as the tires get old no matter whether they are balanced or not. Since the shimmy goes away at high speed, it is obviously not a tire balance issue anyway. There are certain very smooth stretches of pavement where the shimmy goes away, so I have always figured and sometimes read that it is a design flaw with the 944 suspension geometry which causes it to have excessive "road feel," so standard irregularities in the roadway become amplified at freeway speeds.

rgs944

Read this post again. It most likely is a balance problem. Just because it goes away at higher speed does not tell you anything. Just like a lot of guys here, mine started shaking at 60 and it went away at 80. Had this happen on two different 944's. Got a good quality balance on each and problems solved.

safulop

It cannot be balance if it goes away at high speed, it is basic physics.

catfish

It can go away at high speed, according to basic physics. Eventually it may come back at even higher speeds. At some speeds, the unbalances add up to give a vibration but then at other speeds everything cancels out and you don't get much vibration.

catfish

Upon further thought, just to clarify: If you had a perfectly round, balanced tire with one heavy spot, then yes, it would always get worse at higher speed. In reality though, my understanding is you've got a bunch of imperfections in the tire/wheel package that can be averaged out pretty well by balancing. Most of the time the vibrations these imperfections cause cancel each other out, but at certain speeds the imbalances can add up, causing vibration. In my experience the periodicity of vibrations in the steering wheel is slower than the rotational speed of the wheel. The vibrations will then come and go as speed increases.

Makis

Incorrect front wheel alignment can also cause this. Also if the car is not driven often can cause this. Cheap tires also are more prone to vibration.