Concentric Tire Mounting and Balancing
Why it’s important
What is concentric mounting?
In terms of tire mounting, “concentric” simply means that the center of the wheel or rim is in the exact same place as the center of the tire mounted on it.
How do you know if your tires are not properly mounted?
Depending on how non-concentric the assembly is, drivers may or may not feel ride disturbances. If the mounting is bad enough, ride disturbance will be evident immediately. More subtle mismounting may not be noticeable at first, but can lead to irregular wear initiation and, as irregular wear progresses, it can lead to ride disturbance.
How do you maintain a proper mount?
A non-centric mount will never “fix” itself, but once a tire is properly mounted, maintaining proper air pressure will ensure that the tire and wheel stay concentrically mounted.
What is the process for making sure your tires are concentrically mounted?
It’s a simple four-step process. Just remember “Clean, Lube, Align, Check.” Or, memorize the nonsense word “CLAC”, made from the first letters of each step.
Why do clean wheels and tires matter in regards to concentric mounting?
On wheels, bent or dented flanges, rust build-up, dirt or damage can make it impossible for the tire’s bead to seat properly. If the bead can’t seat properly on the flange, the mount will probably be non-concentric. Bead damage or dirt can cause the same problem, so be sure to check the tire as well. This is why you must always clean and inspect wheels and tires carefully.
What role does lubricant play in concentric mounting?
Proper lubrication can reduce bead damage, makes mounting easier, and helps the tire’s bead fit easily into the proper place on the rim flange. Be sure to lubricate both the wheel and tire bead. And remember, avoid both water-based and petroleum- based lubricants. Water-based lubricants can cause both wheels and steel tire cord to rust, while petroleum-based lubricants can destroy rubber over time. We recommend using only a high-quality, vegetable oil-based lubricant for truck tire mounting. Your mounting supplies dealer should be able to provide you with an appropriate lubricant.
How do you align your tires to achieve concentric mounting?
Use the red and yellow dots you find on Bridgestone tires to help minimize radial runout and aid in initial static balance. Be sure to align any dots correctly. Then, making sure that you follow all OSHA, RMA, tire manufacturer and shop procedures, proceed to seat the beads.
How can you check your wheel and tire assembly for concentricity?
Use the tiny ring that’s molded into the tire near the bead, and check its distance from the edge of the bead flange. Check it in at least four locations, 90 degrees apart, and do this on both sides of the tire. The molded ring must be the same distance from the flange in all locations. If you can see a difference, the tire is not concentrically mounted.