Why does a new tire need balancing at all?
No tire is perfectly uniform, and neither is any wheel. The difference is small — often a matter of grams — but a wheel turning around eight hundred times a minute at highway speed turns a few grams of imbalance into a vibration you can feel through the steering wheel and the floor. Balancing finds where that heavy spot sits and counteracts it with small weights on the rim. It is the difference between a new set feeling right and a new set feeling worse than the one it replaced.
