Posted by Sherman in Idaho [108.162.245.23] on Sunday, May 15, 2016 at 17:54:25 :
In Reply to: Re: Installing Balancing Beads posted by Milo in Pa [173.245.54.67] on Sunday, May 15, 2016 at 09:24:37 :
What I concluded is that nobody knows how balancing beads work. They presented several theories, which range from gobbledygook to impossible. A few ounces of beads evenly distributed are not going to affect a rotating mass of a hundred pounds or so. The idea that the beads merely swamp out the effects of an out-of-balance tire is ludicrous. But then they get into how the beads magically redistribute themselves into just the right place, and that part isn't clear either. If they settle into the bulges of the tire, as you might think, they would make the imbalance worse, and most imbalance isn't visible in any change in the interior contour of the tire anyway. Then they get into ways in which bouncing might make them settle into the right spots, but I couldn't follow that theory either. Granted, I'm no expert, but I did pass statics and dynamics in engineering school and I know what angular momentum is and the difference between static and dynamic balance.
I don't doubt that the beads work as claimed -- plenty of people will testify to that. But I do wonder what the real physics principle is that causes them to automagically end up in just the right place.
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