How to Diagnose Out of Round Tire Rims

If there are some vibration in your ride, you're going to want to find out what's going on. One possible diagnosis is an out of round tire rim. Here we will walk you through the process of finding out what's going on.

Instructions

1. Mount the wheel/tire assembly on the balancer and secure it in place.

2. Spin the tire assembly with your hand, and very slowly bring the crayon closer to the tire to mark the tread. If there is a high spot on the tire, the crayon will catch it.

3. Loosen the assembly, turn the tire around 180 degrees, and spin the tire again by hand.

4. Move the crayon in toward the tire, but move it a little to one side of the mark you made before as you try to diagnose out of round tire rims.

5. Check the mark on the tire. If the mark is in the same place as the first mark, then you have mounted the tire properly. Mark the rear flange of the tire to show the location of the high spots.

6. Remove the tire from the rim and rotate it 180 degrees, re-inflate the tire and repeat the above steps. Check the crayon marks to see where they hit. If the mark isn't on the high spot, then the marks on the tire and on the wheel match. No mark is a sign that the low spot that you made on the tire, and the high spot on the rim match to create an assembly that's uniform. But if the high spot remains and the mark's near the rear flange, take off the tire and put the wheel on the assembly by itself, checking for run-out as you spin it when you attempt to diagnose out of round tire rim.

7. Look for movement near the rear flange where the crayon mark is. If you see movement, then there's a chance the wheel is out of round. Check the wheel with a dial indicator to determine the tolerance. If it's not within the proper allowance, then you should reject the rim.