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If alloy wheels are just fitted with an air gun , will I get wheel wobble ? Or have the bolts got to be torqued to a specified degree ? Reason I ask , just had new alloys fitted tyre garage just put them on with an air gun giving the bang bang bang bang noise as the bolts where tightened. Now my steering wobbles . Yes wheels are balanced and have been re checked by 2 diff garages .
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If they have been rechecked by two garages did they not need to remove the wheels to check the balance?
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but and all garages (just my luck) wacked them on with that damned air gun . I cringed asked them to not put them on so tight , they said we have too .
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I could be wrong but is the bang bang bang noise not mean its reaching its torque level? Try taking one of yourself and tightening it by hand and see if it makes any difference?
Failing that I am stumped !
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Have you got a single heavy locking wheelnut on each wheel by any chance? Been made a fool of by that one myself (and a tyre place in Kendal or somewhere of the sort).
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Did they just use the air gun? My local tyre place uses the air gun to do the bolts up, then tightens them with a torque wrench.
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Did they just use the air gun? My local tyre place uses the air gun to do the bolts up, then tightens them with a torque wrench.
My local tyre place too. Never ever trust those air wrenches to do a specified torque
Always thought alloys ahould be torqued
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If the wheel/tyre assemblies are OK, then has the original garage caused some damage to the suspension by jacking the car up in the wrong place? What did they use to raise the car off the ground?
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L\'escargot.
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I've just had my two front tyres replaced and they used the air gun to tighten the wheel nuts (including a locking nut) and I have no problem with vibration. However, I did make sure they used dynamic balancing rather than static balancing.
Andy
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However, I did make sure they used dynamic balancing rather than static balancing.>>
Does anyone use static balancing today. It must be 20 years since I have had a wheel balanced on anything other than a wheel rotating machine thingy?
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Espada III - well if you have a family and need a Lamborghini, what else do you drive?
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Does Andy mean the balancing with the wheels on the car ? I know it can be done but I've not seen it in the tyre places I use.
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As they are new alloys, they MAY be out of true/ not straight/have incorrectlty machined mounting points.
Remove and check with a steel rule on inner and outer rims. Get garage to check wheel alignement first tho...
madf
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Does Andy mean the balancing with the wheels on the car?
>>I know it can be done but I've not seen it in the tyre places I use.
>>
IIRC static balancing is just what it says. i.e. NOT spinning the wheels when identifying what weights are required.
Balancing wheels on the car may be required if parts other than the wheel/tyre are causing vibration.
Once done of course the wheel should be always be re-fitted on the same corner in the same position relative to the hub.
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It is possible a wheel can be balanced perfectly and still give wobble.Balancing does not take into account any run out,this could be the rim or occuring when the wheel is mounted.If you could get hold of a dial guage,or improvise a rig of some sort, you could jack up a wheel and check,give it a spin and see if it runs true.
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IIRC static balancing is just what it says. i.e. NOT spinning the wheels when identifying what weights are required.
There's a little bit more to it than that Henry.
Some tyre balancing machines which spin the wheel up can be set only to measure static imbalance.
Static imbalance is where one part of the wheel is heavier. If you jacked the wheel up, and the brakes weren't binding, the wheel would rotate so the heavy spot was pointing down.
So, as you don't need to spin the wheel to see this kind of imbalance manifest itself, it is called staic imbalance.
A wheel with static imbalance produces a radially directed force at the hub which rotates with the wheel - the balancing machines can measure this force when the wheel spins up.
If you were to take two wheels with the same static imbalance, and mount them back to back (like on the back axle of a truck), but with the heavy spots opposite, you would get no static imbalance. There would be no overall heavy spot, and the wheel would stop at random locations when spun and allowed to come to rest.
However, at speed, when the heavy spot of the outer wheel is generating an upwards radial force, the heavy spot of the inner wheel is generating an equal force, but downwards. Because there is some distance along the axle between these opposite forces, they tend to twist. So, the combination produces a couple which rotates with the wheel.
Because you can't measure this couple without spinning the wheel it is known as dynamic imbalance.
Practically, dynamic balancing is done in two planes, one the front or outer rim of the tyre, and the inner rim. This is why the machine can indicate different weights in different positions on these two faces.
So, just because the balancing machine spins does not mean that it is measuring dynamic imbalance - some can be switched to measure only static imbalance (although most machines nowadays don't bother with the switch, always balancing both static and dynamic together)
Practically, Welshy needs to check that the wheels are true running, and he needs to take his car to somewhere more professional to have his wheels and tyres looked after!
Number_Cruncher
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And, I repeat, he needs to not have a single heavy lockable nut or bolt on each wheel, which can be enough to unbalance it when fitted although it has been properly balanced on the machine. .
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This is true.
A good way to assess if this is likely to be a problem is to consider the mass * radius (mr) product. The out of balance forces are equal to mass * radius * (angular velocity)^2.
The balancing machines don't tend to give readouts of less than 5g at the rim. So, it's quite possible to have balancing errors of, say, 60 gramme centimetres, with the balancing machine still recording zero.
At a typical wheel nut radius, this allows you to have an imbalance of about 12 grammes before it will be comparable with the tolerance of the balancing machine.
Number_Cruncher
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Do the alloys need a spacer ring to fit the locating centre ring on the hub?
Some aftermarket alloys have a standard size hole in the centre and you need the spacer ring to ensure the wheel is correctly centred on the hub.
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as i said last week i use a bubble, but not for retail consumption.
Any decent tyre bay will have a torque adjusted airgun.
Any decent tyre bay should tell you to recheck your nuts/studs after 50 miles.
Your new tyre/tyres could be out of shape you will see this if you jack the car up and spin the wheel.
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\"a little man in a big world/\"
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If the alloys are new to your car, another thing to check is do they fit on the hubs flat and square?
Some years ago, Motor magazine fitted Wolfrace alloys to their Blydenstein Vauxhall Firenze Estate project and had the same problem. Cure was to machine the wheels locally to clear hub protrusion.
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I wasna fu but just had plenty.
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