Quote:
Originally posted by Sion
zooksport2: "With modern balancers, it is difficult to stuff up a balance." you haven't met some of the gene pool pollutants I've worked with then.
"BUT! A question for you! Could you balance a set of low quality tyres on an older style balancer (electronic, but not "computer controlled) and not have a vibration problem, when they are to be fitted to a 5 (or 7) series Beemer? And 2) why is vibration a potential problem on this type of vehicle?" I think we all know my policy on answering questions in this thread. But, I am going to make an exception this time.
1. I do believe I could properly balance those tires. One of the secrets to good balancing on problematic tire/wheel combinations is to find the heavy spot on the wheel, by spinning it on the balancer without a tire mounted. Once you have that, its a relatively simple matter of tire position with respect to the wheel heavy spot. It might take a couple, three tries, after each of which the tire would be repositioned until the heavy spot of the tire was exactly opposite the heavy spot on the wheel.
2. I have no idea what the potential problem on these cars are, as I never had the opportunity to work on one. I would say, however that a BMW owner putting cheap tires on a car like that would be the number one problem. Other possible reasons could include wheel shaped such that only a static (as opposed to dynamic) balance was possible; poor suspension or steering geometry design that magnifies wheel vibration; or wheels that tend to be bent/warped/out of round even when new. So, what do you know about these cars that I do not?
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Back at ya, Sion, Fully agree with you on all those points. Strangely, I have enquiries on a semi-regular basis from expensive vehicle owners wanting cheap tyres..
The 5/7 series Beemer, (and others) have aluminium front suspension, struts, A arms, Control arms, hubs, rotors, calipers et al, ( Though not nesessarily all the above at the same time) which results in a very light "unsprung weight". Because of this, any errors in tyre selection, and balancing will easily show up whilst driving. Owners should be made aware of the ramifications so that a tyre shop is not "held" responsible when the owner complains of ride vibration. In Australia, Nissan Patrol 4WD's have a reknown ride vibration problem. My first question to a potention tyre buyer is " Does your Patrol vibrate?" If the answer is yes, Then I tell him why he can't put cheap tyres on.
OK thats enuff of tyre talk lesson 1.
Next question, please.
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Racing around to come up behind you again. The sun is the same in a relative way but your older, shorter of breath, and one day closer to death" ...pink floyd