Wheels need to be balanced while rotating at a speed great enough to allow the masses within the wheel to affect the movement. Slow rotation will not produce enough centrifugal force to cause the wheel assembly to move off center. The reason that a wheel vibrates is that the mass of steel (or magnesium, or aluminum, et al) combined with the mass of rubber and fiber and steel wire in the tire cannot be made so that all of the product weight is distributed evenly. If the wheel and tire were made in the shape of a stereotypical "Space Ship", such as from the movie "The Day The Earth Stood Still" (come on, if we remember the 1955 Chrysler, we certainly remember that movie!), there would be no problem with "dynamic" balance, because there would be no tendency for the weight move to the axis of rotation, The centrifugal force effect would already be compensated by the fact that the weight would already be directly out from the rotation axis. But since wheels have a wider edge at the circumference, it is necessary to compensate by placing weights as far out to the edges as possible, and certainly to place the two weights, one on the inside, and one on the outside. There was a comment that one guy's car, at 110mph, had no vibration caused by the wheels, but his mirrors were vibrating, and he said the it was partly caused by the engine being "very busy". If the engine, at any speed, were vibrating enough to shake the mirrors, the engine parts would be distributing themselves across the roadway. The vibrating mirrors, and florboards, and steering wheel, are much more likely caused by wheel vibration due to out-of-balance conditions; usually this "dynamic" effect. Mike Higgins 1955 Belvedere Sport Coupe In Farmington, NM; where we are today learning about the "High" of high desert. The temperature this morning was 6 degrees, but we expect a high of 40. At 5300 feet, it does get cold in the desert. -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- Over 25,000 pages of archived Forward Look information can be easily searched at http://www.forwardlook.net/search.htm Powered by Google!
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