Abstract: A chuck is mounted to the hub of an out-of-balance wheel and an indicator stem is connected by means of a ball joint to the chuck. When the wheel is rotated and reaches a velocity such that it tends to oscillate, the indicator stem is moved to an attitude where it extends across the axis of oscillation and is balanced in this position. The rotation of the wheel is then stopped and the position of the indicator stem indicates the location where a weight is needed on the wheel and the approximate amount of weight needed at this position.