Match mounting rotates the tire on the wheel so complementary high and low points reduce total assembly variation.
Balancing corrects mass; match mounting addresses geometry or force.
Mark tire and wheel before demounting.
Measure wheel and tire contributions separately when possible.
Rebalance after indexing.
Why indexing helps
If tire and wheel high points align, total variation can increase. Rotating the tire so high and low points oppose can reduce the assembly result.
Measurement process
Measure wheel radial runout, identify tire or assembly high point, mark references and rotate the tire to the calculated position.
Limits
Match mounting cannot repair a bent wheel, separated tire or excessive structural variation. Replace defective components when limits remain exceeded.
Diagnostic reference
| Finding | Possible meaning | Next check |
|---|---|---|
| High runout | High points may align | Measure and index |
| Large balance weights | Geometry issue possible | Check runout |
| Bent wheel | Optimization limited | Repair or replace |
Workshop procedure
- Measure and mark current condition.
- Measure wheel separately if possible.
- Identify tire high point.
- Demount and rotate tire.
- Reseat, remeasure and rebalance.
Frequently asked questions
Is match mounting balancing?
No. It optimizes geometric or force relationships before final balancing.
Can it fix a bent rim?
No, although it may slightly reduce the combined result.
Why rebalance afterward?
Changing tire position changes mass distribution.
Technical review edition · Published 17 July 2026.