Curing wheel wobble

[Keith Scarfe]

Well I don't think exactly cured, but it is a lot lot better.
I have ALWAYS had wheel wobble on my car and up to now I have assumed it is because the wheels are buckled. Reading all the (numerous) post on here about age of the rims how thin the metal is and how they cant be balanced as they centre on the pegs not the central flange etc I came to the conclusion that I just have to live with it. I considered trying to find somewhere that balances them on the car (there is somewhere near Oxford) - expensive and a bit of a trek or having to buy new minilight rims and am always on the look out for 2nd hand ones on ebay etc. I have had the wheels on a balancing machine probably 4 or 5 times and I have measured the run out and they are within tolerance. Yes a bit of run out and some did need rather a lot of weights to balance but they did show 0 on the machine. But the wobble was always there.
Then I thought of the tyre rather than the rim maybe the cause. They still have loads of tread left but are actually 14 years old so could do with changing anyway. The car has also sat for a few years without moving so I wondered it this could damage the internal structure of the tyre maybe. After reading this thread http://www.lotuselan.net/forums/for-sale-f34/rated-155-tyres-ebay-t31170.html I decided to get a set of the Vredrestien Sprint's. Fitted and wow an immediate noticeable improvement. Like I say not completely gone but much better. The slight wobble comes in now at about 80 now rather than it used to at 60-70 (exactly cruising speed) so it is really quite livable as I don't cruise at 80.
I will see it it gets any worse, but for now it is OK. I guess new minilight type rims will irradicate the wobble as I am sure these rims still arn't the best as the do run out slightly (but within tolerance) both radially and laterally but I do want to keep the originality if I can.
Interesting though, so it is definitely worth changing tyres if they are old and suspect and I got all 4 for ?130 which is the same price as 1 for the modern tin box.
Cheers.
Keith

[ericbushby]

keith,
I also have a buckled wheel. It was my fault! I pranged it on a kerb whilst accelerating too hard on a wet bend.
I know ! I know! I learned that 50 years ago. Well I have just learnt it again.
Do you know what the acceptable tolerances are for lateral and radial errors so that I have something to work towards. I have not done a search for this info, I just thought you might know.
Eric in Burnley
1967 S3SE DHC

[Keith Scarfe]

Not off hand but it is on here somewhere, that is what I checked mine against. You will have to have a bit of a search as I cant find it at the mo. The search on this site is pants. If I find it ill post it.
In this post http://www.lotuselan.net/forums/lotus-suspension-f42/steel-wheel-lateral-runout-t901.html Rohan says 1mm should be the max. I think this is what I used as my benchmark.

[Chancer]

Could it be that they are marginally lighter tyres so need to rotate a little faster before vibrating at the natural frequency of the suspension system?

[billwill]

keith,
I also have a buckled wheel. It was my fault! I pranged it on a kerb whilst accelerating too hard on a wet bend.
I know ! I know! I learned that 50 years ago. Well I have just learned it again.
Do you no what the acceptable tolerances are for lateral and radial errors so that I have something to work towards. I have not done a search for this info, I just thought you might know.
Eric in Burnley
1967 S3SE DHC

I presume you now have TWO buckled wheels, else why is the buckled one not your "get you home" spare wheel and the former spare on the car ?

[ericbushby]

Hello Bill,
I had five good wheels, and the spare is of course on the car. The damaged one is on the garage floor while I keep looking at it ruefully and wondering what can be done. Can anyone straighten a wheel which runs out 3mm and has a dent as well. Also I wonder if it is worth bothering. I think I can sort out the dent in the rim. Otherwise as it still holds air it will be relegated to the boot as you say. It doesn`t cause trouble under 60 MPH.
Eric in Burnley
1967 S3SE DHC

[Galwaylotus]

Then I thought of the tyre rather than the rim maybe the cause. They still have loads of tread left but are actually 14 years old so could do with changing anyway.

Fourteen year old tyres can be lethal!! Car manufacturers usually suggest not running tyres older than six years from date of manufacture as the chemistry of the rubber changes with time and you are looking at potential delamination. Driving on fourteen year old tyres at any speed is a mistake and at 60-70 mph may be fatal.

[StressCraxx]

I had my steel wheels straightened by a local shop that specializes in repairing wheels. They were able to straighten 3 out of 5 of my wheels. The other two were straightened successfully, but somehow they reverted back to close their original runout. Its worth a try though.

The reason I had them straightened was due to a rear a-arm chassis pickup point failure. Low stress - high cycle fatigue failure of the pickup point, from years of vibration from a bent wheel.

I found a set of used Panasport K/O wheels a few years later and the old wheels are now in storage.

Regards,
Dan

[RichardHawkins]

Eric,

A few years ago I did a search in the British Library looking for British Standards that covered steel wheels at the time our cars were current.

BS AU 50 Part 2 section 0 1979 seemed to be the most relevant I could find and gave lateral run out of 1.5mm maximum error as total indicator reading. Diametral run out is given as the same figure.

I bought a steel wheel from a caravan company (the wheel is made by Mefro in Germany) and measured the run out at 0.012" total indicator reading (about 0.3mm)

So it would seem that quite good tolerances 0.3 mm an be achieved for steel wheels, even when used for caravans.

Hope this helps,

Richard Hawkins

[ericbushby]

Richard, Thankyou, we now have a target figure to aim for. How to achieve it may be a different matter but thankyou again.
Eric in Burnley
1967 S3SE DHC (DHC weather tomorrow, I`m off )

[RichardHawkins]

Eric,

I managed to get my wheels to 0.015" total indicator reading, but as my car is still years away from running I don't know if they wobble.

Richard Hawkins

[AHM]

and how they cant be balanced as they centre on the pegs not the central flange

Whilst an interesting theory that the wheel centres on the drive pegs, it is a little implausible.

[Chancer]

I wish that I had your gift for diplomacy

[patrics]

Hi gents
I guess if it centres about the the pegs rather than the spinner cone will depend on the tolerance about the pegs relative to the cone?
For production vehicles wheels are balanced for radially force runout and lateral force runout. Post production it's only normal to do the lateral force runout.
So we only get our wheel partially balanced.

Regards
Steve

[Hawksfield]

Hi All

As the wheels are generally balanced on the cone I have made the peg holes a little larger so that the cone centres the wheel. don't ask the size of the peg hole in the wheel as they were all different by a very small amount. This worked and I have a much smoother drive. Its not perfect as I have some run out on the wheels due to age but acceptable, the only solution is to purchase new alloy wheels.

I have been running like this for two years and was worth the effort.