Balance Bead Calculator - Calculator Academy

Enter the weight of the tire (or tire + wheel assembly) into the calculator to estimate the amount of internal balancing beads needed. Actual bead amounts are typically selected using the bead manufacturer’s chart based on tire size and application.

Balance Bead Estimate (Rule of Thumb)

The following relationship is a rough estimate used by this calculator. In practice, balancing bead amounts are usually chosen from manufacturer charts based on tire size and use.

BB \approx TW / 13

Where BB is the estimated balance bead amount (ounces)
TW is the tire (or tire + wheel assembly) weight in pounds

For this estimate, divide the weight in pounds by 13 to get an approximate bead amount in ounces.

What is a balance bead?

Definition:

Balancing beads are small free-moving beads (often ceramic or glass) installed inside a tire (or tube). As the tire rotates, the beads redistribute to help counter imbalance. They are an alternative to traditional external wheel weights that clip or stick onto the wheel.

How to calculate balance beads?

Example Problem:

The following example outlines how to estimate the weight of balance beads for a tire using the rule-of-thumb above.

First, determine the weight of the tire (or tire + wheel assembly). In this example, the weight is 39 lbs.

Next, use the estimate above to calculate the bead amount in ounces.

BB ≈ TW / 13

BB ≈ 39 / 13

BB ≈ 3.0 ounces

Follow-Up Calculations

If your balance bead calculator says a 35x12.50R17 tire needs about 8 oz of beads, you are also dealing with roughly 110 inches of rollout, so the tire is carrying more circumference as well as more rotating mass. You can estimate your tire rollout to compare that 35-inch setup with a 37-inch tire, since every added inch of diameter changes both road speed and the amount of balancing media that is usually needed.

A 37-inch mud tire that calls for about 8 to 10 oz of beads also raises the wheel-over point, which helps a truck bridge rocks and ruts instead of dropping into them. Use check obstacle clearance to see how much more terrain you can span after a tire-size change, because diameter affects both balance and crawlability.

If the new tire package needs 6 to 8 oz of beads and you add wheel spacers to clear the suspension, the steering geometry changes too — a 1-inch spacer can increase scrub radius enough to make the wheel kick back more on rough roads. You can see how offset changes steering to quantify that effect before the setup goes on the truck, which is especially useful when bigger tires already add weight at the corners.