METHOD FOR SPIN BALANCING TYRES CONTAINING PREVENT-A-FLAT

Normally tyres should be balanced BEFORE the addition of PREVENT-A-FLAT. However, should a tyre become out of balance due to the loss of a balancing weight, or any other reason, it may become necessary to balance the tyre with the PREVENT-A-FLAT installed.

Such balancing is possible through the proper use of SPIN BALANCERS, although the normal techniques used must be modified to allow for the PREVENT-A-FLAT that is now inside the tyre. Computerized Spin-Balancers usually accelerate very rapidly to a speed of about 95kph., then instantly shut off, registering the imbalance condition of the tyre on a digital readout.

When the tyre to be balanced contains PREVENT-A-FLAT, the automatic shut-off mechanism of the machine must be defeated or turned off, so that the operator can control the duration of the rotation. The PREVENT-A-FLAT must have time to circulate around the entire inner tyre/wheel area evenly. A mallet or hammer should be used to assist in the process. It may take several minutes for even distribution of PREVENT-A-FLAT to occur. Then the machine should be allowed to shut off registering any imbalance of the tyre.

The imbalance should be noted and the machine allowed to start and stop in its normal way until the registered imbalance is repeating. Then the appropriate weights are added to the tyre in the normal manner. The tyre balance should then be re-checked and any adjustments made if indicated. The tyre is now in proper balance.

The starting and stopping of the machine simulates rapid acceleration and braking and can assist in distributing PREVENT-A-FLAT evenly around the tyre's inner cavity. This action may be inter-mixed with the period of continuous high speed rotation of the wheel on the balancing machine as described above.

Once the tyre is properly balanced and contains PREVENT-A-FLAT, the resultant balance condition is more nearly perfect than can be achieved with lead weights alone. This is because lead weights are normally calibrated in grams, where PREVENT-A-FLAT distribution is minute. In addition, as a tyre wears from normal use it can alter the balance. PREVENT-A-FLAT will continuously and automatically compensate for such wear, maintaining perfect balance.

Longer tyre life is the reward.