Checking the Balance Machine Accuracy/Repeatability

The balance machine may be out of calibration or in need of maintenance. Perform the following to check the accuracy/repeatability of the balance machine (see Figure 2).

1. Perform steps 1 through 12 from the Mounting Procedure.

2. Turn the balance machine spindle shaft/plate so the previous reference mark is now at the 9 o'clock or 3 o'clock position.

3. Mount the wheel/tire on the machine with the valve stem at the 12 o'clock position.

4. Use the non-rounded measurement mode to balance the wheel again (repeatability must not be over 3 grams and any additional weight must be within 10 degrees of the placement in step 10).

5. If accuracy/repeatability of measurements continue to be over 3 grams, check the calibration or call your wheel balance machine manufacturer for maintenance.

NOTE:
It is highly recommended that balance machines with 40 mm shafts and two-plane calibration capability only be considered when purchasing new equipment. The 40 mm spindle shaft is more durable and less prone to damage and wear. Two-plane calibration greatly increases the accuracy of wheel/tire balancing.