When performing a ring test, it is generally recommended to tap the wheel at multiple points around its circumference to ensure that the entire wheel is checked. This may involve tapping at intervals of every 10-15 degrees or so, depending on the size and shape of the wheel. It is important to make sure that the ring gauge is properly adjusted to make contact with the wheel at each tapping point. The gauge should be placed on the wheel so that it is perpendicular to the wheel's surface, and the contact points should be evenly spaced around the circumference of the wheel. By tapping the wheel at multiple points and observing the movement of the gauge, you can get a sense of whether the wheel is balanced or not. If the gauge moves smoothly around the wheel without any wobbling or binding, the wheel is likely to be in good condition. If the gauge exhibits any wobbling or binding, the wheel may be out of balance and should be checked and corrected as necessary.