Wheel Balancing

Wheel Imbalance Reasons:

• A new tyre may look perfectly round and balanced, but there are small variations in weight around its circumference. Tyres also have slight weight imbalances, whether from a joining point of the plies or a slight deviation from perfectly round.

• Wheel rims also contribute to imbalances. The wheel's valve stem hole reduces a small amount of weight from that side of the wheel.

• Even if the wheel was perfectly balanced, weight distribution around its circumference becomes uneven with wear. This change in weight causes the wheels to become unbalanced.

• At high speeds, a small imbalance in weight becomes a large imbalance in centrifugal force, causing the wheel/tyre assembly to rotate with stomping motion. This results in vibration in the car as well as some very irregular and damaging wear on the tyres.

• Hitting a pothole or a curb with tyre or rim makes a previously balanced wheel unbalanced.

• Wheel impacts and the normal stresses of driving may cause a wheel balancing weight to become dislodged. In such a case, immediate onset of vibration will be experienced

Symptoms: • Vibration/wobble in the steering wheel at certain highway

speeds. • Vibration in the seat or floorboard at certain highway speeds. • Wear pattern on the tyres

Wheel Imbalance

Effects

• Accelerated and uneven tyre wear.

• Undue load on suspension.

• Damage to steering components.

• Driver fatigue

• Reduced traction and steering control

• Increased fuel consumption

Wheel Imbalance

• Mark the wheels in relation to their location on the vehicle and then remove them. This eliminates chance of mixing up the wheel’s position to the hub when replacing it.

• Check and adjust the tyre pressure before balancing the wheel

• Remove any old weights from the wheel and clean it thoroughly. Make sure the valve stem cap is installed

• Mount the wheel and tyre on the balancer, putting the inside part of the tyre on first. Secure the wheel with the hub nut assembly.

• Determine balancing settings

Wheel Balancing Procedure

• Turn the balancer on to rotate the wheel. Read the balancing machine analysis, which tells whether the wheel is out of balance, and if so how much weight to use and where to put it to balance the wheel.

• Correct the balance: Install the weights recommended by the machines display, using the correct fixing method for the weights.

• Recheck: Again rotate the wheel to check for accuracy of the balancing and to confirm that balance has been achieved (A reading of zero on both sides of the wheel means the wheel is ready to reinstall on the vehicle)

• Repeat the process for the rest of the wheels and tyres. • Refit the wheels and tyres to the vehicle applying proper

rotation

Wheel Balancing Procedure

Balancing Weights

Balancing Weight Material

• Lead: Very high Density (11.3), small size for given weight, highly toxic and hazardous, not used now

• Steel: High Density (7.8), non toxic, non hazardous, prone to

corrosion, easily recyclable, poor appearance, widely used • Zinc: Low Density(6.6), non toxic, low hazard, corrosion

resistant, good appearance, widely used