20" wheel balancing problems
Discussion
Has anyone had any problems with balancing 20" Porsche wheels? Specifically 981/991?
I did my first tyre change recently (from factory pitted Pirellis) and despite being an awful tyre the car was as smooth as silk.
I had Goodyear Asymmetric 2 N rated fitted and the wheel wobble on the motorway as awful, the garage was apologetic, they re calibrated their machine and tried again but no luck. I tried another garage who were better but again the steering wheel was shaking annoyingly at 60mph.
In the end I drove to the other side of the country to use a friends tyre balancing machine which he has in his garage at home. We examined each wheel and tyre for damage or runout etc., and everything seemed perfect.
We calibrated his machine and re-balanced the wheels as accurately as we could, it's an improvement by 99% but the car isn't as smooth as it was. I can live with it but it got me wondering if anyone else has had a similar problem?
The only thing I can think of is the tyres have a minor defect that the wheel balance machine isn't picking up? I could either try a newer more accurate wheel balancer or try road force balancing (they balance the tyre and wheel separately).
I did my first tyre change recently (from factory pitted Pirellis) and despite being an awful tyre the car was as smooth as silk.
I had Goodyear Asymmetric 2 N rated fitted and the wheel wobble on the motorway as awful, the garage was apologetic, they re calibrated their machine and tried again but no luck. I tried another garage who were better but again the steering wheel was shaking annoyingly at 60mph.
In the end I drove to the other side of the country to use a friends tyre balancing machine which he has in his garage at home. We examined each wheel and tyre for damage or runout etc., and everything seemed perfect.
We calibrated his machine and re-balanced the wheels as accurately as we could, it's an improvement by 99% but the car isn't as smooth as it was. I can live with it but it got me wondering if anyone else has had a similar problem?
The only thing I can think of is the tyres have a minor defect that the wheel balance machine isn't picking up? I could either try a newer more accurate wheel balancer or try road force balancing (they balance the tyre and wheel separately).
I'm really fussy about wheel inbalance myself.
I think a front wheel slight inbalance tends to be more noticeable on rear wheel drive cars and it doesn't take much to notice this through the steering wheel.
Assuming the balancing machine is correctly calibrated, it still requires the fitter to place the weights exactly in the correct position and also on the wider wheels to balance the wheel with weights (usually) placed on the inner and outer parts of the wheel..
I suspect you may have this in conjunction with a badly inbalanced tyre itself and the wheel balance process is not able to fully overcome the issue in the same way that you can't balance out a slightly buckled alloy.
Personally I'd go to a Porsche specialist or even an OPC and get them to take the time to get them spot on, (obviously after explaining the issue with them).
I've had wheels in the past that felt fine in warm weather and yet had a slight inbalance on really cold days, so it doesn't always appear to be an exact science. I'd also clean the inside of the wheel and remove and thicker carbon deposits etc and get the tyre pressure where you want it before you start the processs. Also try out a few different road surfaces because this can also have a bearing on steering feel.
I think a front wheel slight inbalance tends to be more noticeable on rear wheel drive cars and it doesn't take much to notice this through the steering wheel.
Assuming the balancing machine is correctly calibrated, it still requires the fitter to place the weights exactly in the correct position and also on the wider wheels to balance the wheel with weights (usually) placed on the inner and outer parts of the wheel..
I suspect you may have this in conjunction with a badly inbalanced tyre itself and the wheel balance process is not able to fully overcome the issue in the same way that you can't balance out a slightly buckled alloy.
Personally I'd go to a Porsche specialist or even an OPC and get them to take the time to get them spot on, (obviously after explaining the issue with them).
I've had wheels in the past that felt fine in warm weather and yet had a slight inbalance on really cold days, so it doesn't always appear to be an exact science. I'd also clean the inside of the wheel and remove and thicker carbon deposits etc and get the tyre pressure where you want it before you start the processs. Also try out a few different road surfaces because this can also have a bearing on steering feel.
My 2 cents... I have no idea how meticulous your tyre fitters are, and without wanting to do them a disservice without knowing what they have done I would just recommend you go to some fitters that have all the correct equipment, training and have good attention to detail. I use one of the Pirelli Performance centres that came in the top dozen of the annual performance audits. A quick google search will get you a list of them. The one closest to me that I am happy with is Micheldever in Hampshire. The #1 rated place is near Birmingham I think.
If there is an out of specification defect with the tyre you should just be able to insist on a replacement.
If there is an out of specification defect with the tyre you should just be able to insist on a replacement.
I have OCD about this stuff and have spent far too long over the years worrying about it...
About ten years ago, I found a tyre shop that gets it right, and I make an eighty mile round trip to get all my tyres fitted there. I get through about half a dozen sets a year across three cars due to all the road mileage/ track days etc., so it was worth finding the right guys.
In summary, I think I'd say: all tyres are not created equal, and there is a huge variation in the capability of tyre fitting equipment and the willingness/ ability of tyre shops to use it.
I found this useful article which explains a lot of the background here: http://www.tirereview.com/when-is-it-overkill/
About ten years ago, I found a tyre shop that gets it right, and I make an eighty mile round trip to get all my tyres fitted there. I get through about half a dozen sets a year across three cars due to all the road mileage/ track days etc., so it was worth finding the right guys.
In summary, I think I'd say: all tyres are not created equal, and there is a huge variation in the capability of tyre fitting equipment and the willingness/ ability of tyre shops to use it.
I found this useful article which explains a lot of the background here: http://www.tirereview.com/when-is-it-overkill/
While I appreciate not all tyre garages are equal I doubt they will be able to better balance the wheels than what they are now, unless they have significantly superior equipment (and training).
I am going to leave them how they are but it would be nice to know if other people have had similar experiences. It would not be the first time that I have bought a set of Goodyear Asymmetric tyres that have been defective/questionable build quality.
I am going to leave them how they are but it would be nice to know if other people have had similar experiences. It would not be the first time that I have bought a set of Goodyear Asymmetric tyres that have been defective/questionable build quality.
SkinnyPete said:
While I appreciate not all tyre garages are equal I doubt they will be able to better balance the wheels than what they are now, unless they have significantly superior equipment (and training).
Significantly better equipment is exactly where hunter road force balancing comes in.Sorry of these sound like noddy questions but...
At the start of subsequent balance sessions were the wheels checked to see if they were out of balance or were the weights just stripped off and a fresh start was made?
And I'm guessing/hoping that when the last weight was put on the wheels were checked once more and it was confirmed that the last weight put in place resulted in a fully balance wheel?
Does the problem get worse over time?
And unlikely if the tyres haven't been removed since first installed but have they moved on the rims?
Have you tried contacting Goodyear?
At the start of subsequent balance sessions were the wheels checked to see if they were out of balance or were the weights just stripped off and a fresh start was made?
And I'm guessing/hoping that when the last weight was put on the wheels were checked once more and it was confirmed that the last weight put in place resulted in a fully balance wheel?
Does the problem get worse over time?
And unlikely if the tyres haven't been removed since first installed but have they moved on the rims?
Have you tried contacting Goodyear?
AW10 said:
Sorry of these sound like noddy questions but...
At the start of subsequent balance sessions were the wheels checked to see if they were out of balance or were the weights just stripped off and a fresh start was made?
And I'm guessing/hoping that when the last weight was put on the wheels were checked once more and it was confirmed that the last weight put in place resulted in a fully balance wheel?
Does the problem get worse over time?
And unlikely if the tyres haven't been removed since first installed but have they moved on the rims?
Have you tried contacting Goodyear?
When I balanced the wheels myself I checked the existing balance, they were out significantly (e.g. 100g a wheel), I then removed the weights and checked again, 3 of the wheels balanced better with no weights at all.At the start of subsequent balance sessions were the wheels checked to see if they were out of balance or were the weights just stripped off and a fresh start was made?
And I'm guessing/hoping that when the last weight was put on the wheels were checked once more and it was confirmed that the last weight put in place resulted in a fully balance wheel?
Does the problem get worse over time?
And unlikely if the tyres haven't been removed since first installed but have they moved on the rims?
Have you tried contacting Goodyear?
After I had added the weights I checked them once again and always got the remaining weight down to 1-5g. I have not refitted the tyres and they haven't moved on the rim either, I know this because the coloured dot markings are aligned with the valve stem.
I don't think the problem gets worse over time although the problem is so subtle that its unnoticeable on certain surfaces. I haven't contacted goodyear.
find a company near you that has a Hunter GSP9700. It is the only machine I use.
It will measure the run out of the alloys and more importantly check the high and low spot of a tyre, I have had a tyres before where the road force created causes vibrations.
The key is though the machine shows this so its very easy to get a replacement from the manufacturer or retailer.
I tend to have alloys 19" or upwards and I am very very fussy about vibraitons and balancing
It will measure the run out of the alloys and more importantly check the high and low spot of a tyre, I have had a tyres before where the road force created causes vibrations.
The key is though the machine shows this so its very easy to get a replacement from the manufacturer or retailer.
I tend to have alloys 19" or upwards and I am very very fussy about vibraitons and balancing
SkinnyPete said:
Thanks!
Shame their website doesn't allow you to search for locations in UK though.
Their website is not ideal, I beleive they do have a search page for UK dealers. As far as i am aware quite a few Porsche garages do use them, all of bentley of them and some independant garages too. Shame their website doesn't allow you to search for locations in UK though.
Ill see if I can find the UK search page even though its not a comprehensive list!
SkinnyPete said:
Shame their website doesn't allow you to search for locations in UK though.
Yes it does - http://www.balancemycar.co.uk/Jakg said:
SkinnyPete said:
Shame their website doesn't allow you to search for locations in UK though.
Yes it does - http://www.balancemycar.co.uk/SkinnyPete said:
Cheers guys. So would you say the Hunter machine is a fail safe way to get the balance spot on?
Closest place to me wants £30 a wheel which seems reasonable given the annoyance it will solve, in future I will just pay the extra!
I would say so. Closest place to me wants £30 a wheel which seems reasonable given the annoyance it will solve, in future I will just pay the extra!
Generally if you have a vibration from the wheels it can only point to two things: the alloy or the tyres.
If the alloy is damaged and out of round the machine will pick up on this as there is a measuring tool which should be used first to measure if the alloy is within tollerance and of course the user of the machine should also do a visual check.
If the tyre has a fault in it then the machine will 100% pick this up and will say there is too much excess ft lb of force generated. The machine at that point will try to match up the high spot of the alloy with the low spot of the tyre and try and balance this out and will spin again to see the rate. Either it will go in the amber/green area of the graph meaning its fine now or go into the red: it will state EXCESSIVE ROAD FORCE.
If its just tipped into this section then you should be fine as if the tyres are generally new then it will fix itself within the first 100 miles if its significantly into the red then its a case of getting it swapped from the manufacturer or retailer.
I stopped wasting my time going to any other garage or using any other balancing machine, I have been to BMW, mercedes, other independants, new blackcircle garages and if their machine says balanced then they have no clue what so ever on how to resolve the issue.
30 pounds a wheels seems about right, its best to get it done right first time.
Ps If I remember correctly normal wheels balancing machines only spin up to a rate of 30mph. The Hunter is tested at a much higher speed, 50 or 70mph coupled with the road force measuring tool. Its as good as its going to get.
Edited by XMT on Wednesday 20th September 16:23
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