Tire or wheel balancing is the unique process where you equalize the weight of the combined tire and wheel assembly so that it spins smoothly at high speeds. Balancing involves placing the wheel/tire assembly on a balancer which centers the wheel and spins it in order to determine where the weights should go.
We all know how important it is to balance your tires about every 5,000 miles mainly due to the fact that tires become unbalanced unevenly so when you multiply that times 4 tires, imbalance can cause serious vibration at high speeds. Unbalanced tires also put uneven pressure on the treads. Tires will get too hot and wear unevenly and tire imbalance can also strain the wheel bearings as well as the suspension system. So whether you’re an auto shop owner or a simple enthusiast, you’re going to want to purchase a wheel balancer to suit your needs.
What causes vehicle vibration?
Tire and wheel imbalance is one of the most likely causes of vehicle vibration. Other causes can be related to drivetrain issues and / or bent components. Tire and wheel imbalance can result in a cupped tire wear pattern, traction loss and premature wear to suspension and steering parts.
The front tires produce more noticeable symptoms than the rear when out of balance due to the translation through the suspension and steering components and the feedback felt at the steering wheel. Vibrations from a rear imbalance may not be as obvious, but will still result in tire wear.
Tire imbalance results when the weight of a tire's materials is not distributed equally throughout the tire thus resulting in the tire being heavier on one side than the other. The imbalance can be caused by issues in manufacturing, or from tire wear. New tires will have minor imbalances that are correctable by adding a wheel weight to a specified location to counter the effect of the imbalance. If excessive weight amounts are needed to balance the tire it may be an indication of a defective tire or that the tire may be incorrectly seated on the wheel rim.
It is possible to balance an out-of-round tire and wheel assembly and still have vibration due to wheel hop (also call wheel tramp). It should be noted that runout of less than 0.030" will not typically cause a noticeable vibration. However, runout of more than 0.125" is recommended for replacement of the tire or wheel. Although it is theoretically possible to balance a square tire and wheel, it does not mean that it will roll smoothly.
Before we begin by identifying the different types of wheel balancers available it is best if we explain the two most common ways to balance a tire and wheel assembly. The first is “Static” balancing which is done with the assembly stationary and the second is known as “Dynamic” balancing and it requires the wheel and tire to be rotating. Both types can improve tire wear and reduce tire disturbances. About 95% of modern wheel balancers come with both of these options but the more practical and faster way to balance your wheels is with the dynamic option.
•Static Wheel Balancing
Static wheel balancing is for wheels that will take weight only on the inside of the wheel. Static balancing uses only one spot to place the wheel weights that measures the imbalance. It is mostly used on heavy truck tires. The imbalance is measured by a static balancing machine where the tire is placed on its vertical axis on a non-rotating spindle tool. In retail shops these balancers are usually non-rotating bubble balancers in which the magnitude and angle of the unbalanced can be seen by looking at the center bubble in an oil-filled glass sighting gauge. Nowadays, this method is used in very few shops. It has been replaced by the more effective method of dynamic wheel balancing.
•Dynamic Wheel Balancing
Dynamic balancing requires the wheels to be rotating and it is an improvement over the static technique. With this technique there are weights that are added to both the inside and the outside of the wheels. In tire retail shops, tire/wheel assemblies are checked on a spin balancer that lets you know the amount and angle of unbalance. These weights are then fitted to the outer and inner flanges of the wheel. It is the better of the two types of balancing techniques because both couple and static forces are measured and corrected.
Buying the correct balancer is critical to the success of your shop. Knowing what to look for and what features make certain balancers better than others will make your life easier and your profits higher.