Technical Service Bulletins

Out Of Round Condition

Checking For An Out-Of-Round Condition

To check for an out-of-round condition, secure a pointer tool so that it will be perfectly steady. Bring the tool to the object (tire or wheel) to be checked. As it touches the object, back off a slight amount. This will provide a uniform distance between the tool and the closest portion of the object being tested. If the distance between the two opens and closes visually, this indicates an out-of-round condition. The more the distance opens and closes, the more out-of-round the object is.

Pointer Tool

You may utilize any object as a pointer tool. It is not necessary to use a sharp object. A sharp point may actually hinder visual inspection of the distance between the tool and the portion of the tire being checked.

Always spin the tire on a high speed spin balancer.

Tire

The out-of-round condition is usually more pronounced in the tread area. Using the pointing tool as described above, check the outer edge of the tread, then the center of the tread and finally the inner edge of the tread.

Wheel

A wheel can be bent or out-of-round and may cause one kind of problem or aggravate another kind of problem. Using the pointer tool as described above, check the wheel both on the front edge for in and out movement and again on the edge closest to the tire for up and down movement.