Impossible to balance wheel ... two shops already failed ..., New tyres didn't help ... Options

[johannes]

I bought a set of Mahle with tyres.
I brought them to a shop to have them balanced.
When I put them on the car it started to vibrate at 90 to 120 kmh (55 to 75 Mph)
Brought it back to the shop, redid the balance, didn't help. They say, the tyres may be warped. I bought them a new set of tyres, let it balance ... didn't help.
They sent me to another shop that has a better machine. They put (a lot of)weigths inside and outside the rim (ugly), but it didn't helped.
The problem occured when I bought these rims I figure they may be bent ...
Could this old and wise guy be right ?
http://www.youtube.com/watch?v=PeclYZQCyso

Any advices ...

[gregrobbins]

Check to see if they are bent or out of round wheel. If its not too bad, either can be fixed.

[Katmanken]

First, I'd loosen the lug bolts and properly retorque the wheels onto the car with the cross torque sequence. Shops use high power air tools and when they don't use the cross torque sequence, can bend the wheel. Sometimes loosening and retightening the lug bolts solves the problem

You need to measure the rims to see if they are bent.

You can do this on the car by jacking up one wheel so it doesn't touch the ground and spinning the wheel while measuring the rim movement.

Two possible rim movements. If it's bent from a side hit, face the wheel like you want to remove the lug bolts. Place a dial indicator at the edge of the rim so that the probe of the indicator is parallel to the axle and touching the edge of the rim next to the tire. Spin the wheel. If the rim is bent, the probe of the indicator will move in and out along the axis parallel to the axle.

The other bend to a rim comes from a front impact such as a curb or pothole. In that case, the rim is no longer round and a dial indicator can also tell.

Sometimes you get both.

If the rims are OK, it's probably the tires.

[Bartlett 914]

There has been some discussion about Lug-centric and Hub-centric wheels. I am not sure if this is an issue here but maybe this thread could be a start to see if this could be your problem.

hub vs lug centric thread

[charliew]

I have original bbs wheels on my fiero and everytime I get new tires they tell me the wheel is bent and they are, two of them with no apparent damage. It still rides great up to it's max speed of 120mph. Their only bent about .100 and it's two wheels and I rotate them and have yet to notice any problems. The shops notice it when they are balancing the wheels. If the wheel and tire can be balanced on the machine, it's the rotor and hub assy. In the late 70's I had toyota gt's with aluminum wheels and everytime I would replace the factory tires the shops could never get the balance as good as the factory balance. You might need a better tire shop. Two sets of tires is a little suspect.

[computers4kids]

Not sure about Mahles, but Pedrinis have early and late designs (lates are hub centric) which could make a difference depending on whether you have early or late hubs on your car. If you have a mixture on your car and when the wheels were removed for tires they might have been moved around.

Trying to remember, but as I recall earlys only fit on early hubs (seat correctly), while the lates will fit late or early hubs. Just a thought...

[ericread]

When I was having similar problems (mine was rectified by replacing the tires) I was able to minimize the problem somewhat by identifying the offending the wheels and placing them on the rear axle. This allowed my front-end to be a bit more manageable at the higher speeds.

But what was said in the previous posts is absolutely on target - identify the offending wheel(s) and work from there.

Good luck!

Eric Read

[johannes]

Thank you for your advices ...

I have just lifted the car to check the rim and here is the result !...

V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V

>>>
What a moron !
Now I know the caliper is close to the rim ...

[charliew]

Nice sweater, damn that looks a little sore. It's 90f and about 80% humidity here. I'm trying to get the pool going. I cut two fingers on my only good hand on some ss sheetmetal yesterday carrying it the wrong way.

[tradisrad]

I've found that having the tires balanced on the car gets rid of the shaking. this is especially true with the low profile tires

[Katmanken]

At least you still have the finger.

Ken

[johannes]

At least you still have the finger.

Ken

Yes ! ... it helps, I am comics artist ! ...

I've found that having the tires balanced on the car gets rid of the shaking. this is especially true with the low profile tires

Tires balanced on the car ? How can you do that ?


(IMG:style_emoticons/default/blink.gif)

[McMark]

Pull the tire and have them test the balance on the bare wheel.

[Drums66]

First, I'd loosen the lug bolts and properly retorque the wheels onto the car with the cross torque sequence. it's probably the tires.

I think this is your problem (IMG:style_emoticons/default/idea.gif)
this has happened to me before! (IMG:style_emoticons/default/shades.gif)

[Downunderman]

Are the front wheel bearings properly adjusted so there is no slop?

[jsayre914]

Yes ! ... it helps, I am comics artist ! ...

what comic?

[aircooledtechguy]

Are the front wheel bearings properly adjusted so there is no slop?

(IMG:style_emoticons/default/agree.gif) I had a high-speed shake when I first bought my car and this is exactly what is was.

Anyone here use balancing beads?? I used these on my wife's minivan and they work incredibly well and the tires are wearing VERY evenly (well as evenly as they can with Ms. Andretti at the wheel). The 914 will get them when I up-grade the tires.

[tradisrad]

johannes, there are two shops in my area that have a tool that they roll up to the car and they can spin the tire and balance it. I think its called strobe balancing.

This link is not exactly what I was looking for but it is an example of the equipment used: http://www.hunter.com/PUB/PRODUCT/balancer/900T-1/index.htm
can you find this sort of service in France?

the third paragraph of thie lotus article tells about it: http://www.lotuselan.net/publish/care_n_re...el_wheels.shtml

[johannes]

First, I'd loosen the lug bolts and properly retorque the wheels onto the car with the cross torque sequence. it's probably the tires.

I think this is your problem (IMG:style_emoticons/default/idea.gif)
this has happened to me before! (IMG:style_emoticons/default/shades.gif)

I'll try that as soon as my finger will be OK again

Are the front wheel bearings properly adjusted so there is no slop?

Yes, it has be done, and the front suspension is in good shape. You can't move the weel with your hands. Everything is tight

johannes, there are two shops in my area that have a tool that they roll up to the car and they can spin the tire and balance it. I think its called strobe balancing.

I haven't seen that before. I'll ask around. Thank you for the advice.

what comic?

This one ... http://HMSbd.com you can watch the trailer on the top of the webpage

[Bartlett 914]

Anyone here use balancing beads?? I used these on my wife's minivan and they work incredibly well and the tires are wearing VERY evenly (well as evenly as they can with Ms. Andretti at the wheel). The 914 will get them when I up-grade the tires.

Sorry for the hijack but the beads look interesting. If these work and fit through the valve stem, why wouldn't small steel balls work?