NANO

WHEELS AND TYRES 475 SUSPENSION WHEEL RUNOUT Wheel runout is because of poor bead seating on the rim. Poor bead seating is usually the result of improper mounting or the use of improperly made wheels. Basically there are two types of run-out : (a) Radial runout: An "out-of-round" situation where vibrations are produced as thewheel spindlemoves up and down. (b) Lateral runout: A side-to-side or wobbling movement of the tyre and wheel. Procedure to perform a wheel lateral and radial run out check is as given below : 1. Remove wheel covers or wheel caps. 2. Mount the wheel on the vehicle or wheel balancer. If on the vehicle, properly lift and support the vehicle such that wheels can turn freely. 3. Position a dial indicator on a rigid fixture. 4. For lateral run out check, position the indicator point horizontally against the side of the wheel rim flange. For a radial runout check position the indicator point vertically against the tyre mounting surface of the wheel rim flange. 5. Slowly rotate the wheel one full revolution while observing the dial indicator. 6. Rotate the wheel to the position where the lowest dial indicator reading was obtained. 7. Zero out the dial indicator. 8. Slowly rotate the wheel one full revolution while observing the dial indicator. 9. Record the highest dial indicator reading. Disregard any indicator readings caused by welds, paint runs, scratches etc. 10. Perform lateral and radial run out checks on both inboard and outboard sides of the wheel. 11. Compare each reading with the specified values (as given below) If the run out is greater than the specification, the wheel must be replaced. Run Out Checking Locations Radial run Lateral run out limit out limit Steel wheel / 1.14 mm 1.4 mm Alloy wheel