Wheel Alignment and Tyre Balancing
Highlights
Wheel Alignment
Wheel alignment is an issue that comes about due to the gradual weakening of the linkages in a vehicle's steering system and suspension setup. A vehicle with improper wheel alignment can result in a substantial reduction in the tyres' life. Besides standard wear and tear, hitting a bump or driving on bad roads can also sometimes lead to misalignment. Some of the issue's major symptoms include abnormal wearing of different tyres, inability of the vehicle to maintain a straight line or if the steering wheel doesn't return to its original position as easily as it should. If while driving, you observe any of the above issues, it's best to go to a proper tyre centre and get your vehicle's wheel alignment checked. In the case of wheel misalignment, there are three factors that are tested - camber, caster and toe.1) Camber:
Camber misalignment is when the top of the tyres are tilting inwards too much whereas positive camber is when they're tilting outwards at a greater than normal angle. It's caused by the wearing of linkage elements and can lead to abnormal wear and tear of tyres. This issue is fixed by mechanically tightening the linkages or by replacing the worn parts.
2) Caster:
Caster refers to the angle at which the suspension sits on the steered wheel with respect to the vertical axis of the wheel when viewed from the side. Caster angles are adjusted in order to get the steering wheel to centre itself after receiving a steer-input.
Positive caster is when the steering axis ends ahead of the longitudinal axis of the wheel whereas negative caster is when the steering axis angles in from ahead of the wheel's longitudinal axis and ends before it.
Caster angle misalignment issues are caused by the wear and tear of linkage elements such as the strut or control arm and can be fixed by replacement or by re-shaping the bent or worn out component.
3) Toe:
The toe angle is basically the angle between the top-down profile of the wheel and the axis along which straight-line motion is expected to occur. Toe-in and out refer to whether the wheels are excessively pointing inwards or outwards respectively. In the case of cars, the front wheels are always less likely to undergo imbalanced wear and tear due to toe-angle misalignment as compared to the rear wheels because both are connected to the steering system and hence bear equal wear and tear even if they aren't aligned. The rear wheels are individual units so if one is aligned and the other isn't then the difference in wear and tear between both units will be substantial. The toe-angle is adjusted by shortening or lengthening the tie-rod (part of a vehicles steering system).
Tyre Balancing
Proper tyre balancing is another important aspect that helps keep your tyres in good shape. Tyre balancing is performed to check for tyre imbalance. The test is performed by mounting a properly-inflated tyre and wheel setup on a spinning machine which determines the point of imbalance and the point at which weight must be added to fix the tyre balancing issue. Wheel weights are added to the rim to counteract the imbalance before the entire wheel and tyre setup is re-checked on the machine. Loss in balance is caused by the eroding of rubber-mass from the tyres over time.
Also Read: Wheel Alignment: All You Need to Know
Last Updated on December 18, 2015