I recently got a brand new pair of front tyres for my 2 year old A4, and initially has a few problems with the balance of these wheels which was sorted out by the tyre services involved. However, since getting these new tyres, (change from Conti Sport Contact 2's to Cont Premium Contact 2's), I have had a slight jitter in the steering at between 60 and 80 varying in intensity from undetectable to noticeable depending on road surface.
The car has done 38K miles and I have never bashed any kerbs or suchlike, can this be the symptomm of wheel allignment being hightened by the different tyre tread pattern ?
I also find the steering lighter than it was before with the same pressures I have always used.
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Did you have the tracking/wheel alignment done as well ? No point fitting new tyres without having the tracking done !
The wobble is due to poorly balanced wheels -I had a great deal of problems recently, which I ended up using another local firm after the fitter at the first business even screwed up the tracking (off centred steering wheel) and three attempts at balancing. It's all down to the fitter ! Some are fantastic, others not so.
Go back to the garage !
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No point fitting new tyres without having the tracking done !
That would depend on the condition of the old tyres. If they had worn down evenly, with no signs of toeing in or out, then there is no point in having the tracking checked.
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>>I have had a slight jitter in the steering at between 60 and 80 varying in intensity from undetectable to noticeable depending on road surface.
If by jitter, you mean a vibration through the steering wheel, at the speeds you mention, this is likely to be dynamic imbalance of the front wheels. Either take it back to the place where you got your tyres fitted and complain, or find somewhere that knows what they are doing.
As DD correctly says, changing the tyres does not change the suspension alignment - if the tracking was good before you fitted new tyres, it will still be good. i.e., I can't agree with the statement below - the number of people offering a tracking service is, sadly, many more than those who know their onions!
No point fitting new tyres without having the tracking done !
Number_Cruncher
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I would have thought it was always worth having tracking checked, even when rotating tyres - what is to say you could have knocked it out in the last few hundred miles before the new ones are fitted - you may not know if the other half did it (male or female) !
Then again what is to say you won't do it shortly after ?
It's usually a free check anyway - any half decent establishment will tell you if it doesn't need doing.
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The wobble is due to poorly balanced wheels -I had a great deal of problems recently, which I ended up using another local firm after the fitter at the first business even screwed up the tracking (off centred steering wheel) and three attempts at balancing. It's all down to the fitter ! Some are fantastic, others not so.
I have had my wheels balanced 3 times, initially I went back to the tyre supplier and hes said that one wheel was 40g out and rectified this.
I was still unhappy with the balance, so I went to a French tyre services on holiday, and they said that one wheel was 20g out and rectified this also.
I am now very mistrustful of the capabilities of wheel balancers I have to say, and have had a lot of problems over the years with this same issue. Is it down to infrequent calibration of the balancing machines ?
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>>I am now very mistrustful of the capabilities of wheel balancers I have to say, and have had a lot of problems over the years with this same issue. Is it down to infrequent calibration of the balancing machines ?
Yes, the machines, when set up properly, *and* used properly are excellent, but, it is difficult finding somewhere to do the job properly.
Some machines do have the facility to increase their sensitivity - for problem wheels.
Happily, calibration isn't a big deal, because when balance is acheived, the measurement of out of balance vibration should be zero, so, the slope of the calibration line isn't hugely important* - only that the accelerometers or force transducers (depending on model) read zero when the acceleration / force really is zero.
The only importance of the calibration slope is to reduce the number of iterations required to acheive balance.
Number_Cruncher
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No idea how common they are, but see if there's someone near you that has a Hunter road force ballancer (there's a centre locator on the page too):
www.pro-align.co.uk/products/balancers/psbalhunter...m
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I think most balancers are similar in ability, its thye person using it that can make a difference!
Find a independant tyre supplier, tell him your problem and I guarantee he would sort it, including identyfying if it is a tyre/wheel problem or something elsewhere on car.
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Update :- I have now finally found a tyre services which knows how to balance wheels !!
There was nothing wrong with my wheel allignment as I originally suspected, but on my 4th wheel balancing trip hooray the car now drives as smooth as silk. Yet again the tyre place I went to found 20g and 15g of imbalance on my two front wheels. This is bound to have an effect on speeds over 50 mph I think.
This begs the question, why are tyre services so sloppy on wheel balance, or are they just too lazy to check the calibration of their machines and use them properly ? or are a lot of the wheel balancing machines out there a bit worn and knackered ?
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This begs the question, why are tyre services so sloppy on wheel balance, or are they just too lazy to check the calibration of their machines and use them properly ?
Or maybe the tyres have slipped slightly on the rim since being fitted. I presume you took it easy for a while to let the tyres bed in and adhere to the wheel rim?
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This is a valid point which I can't realy answer. I guess in future I wight put a small dot of paint on the rim and tyre to see if this has happened.
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Some fitters are better than others - have had exactly the same problem on wheels that have been fitted to rims for some time, but on swapping (front to rear) and re-balanced / tracked - out of balance. Good fitters are worth their weight in gold !
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