Cars and Bikes

Wednesday, 13 February 2008


A wheel alignment is a process involved in making sure all yours tyres are pointing in the right direction. The biggest giveaways your alignment is out, is a wear pattern in the thread that is bias to one side more than the other due to incorrect camber. In some cases, the vehicles may pull to one sides or not willingly travel in a straight line. In certain Jeep line-up (CJ, XJ, ZJ and WJ), incorrect alignment and wheel balance may trigger a “Death Wobble”, the front wheel shaking unsynchronizely in normal driving speed.

Four-wheel alignment makes sure that the rear wheels follow the front wheels in a parallel path. Different manufacturers set different specifications for the angles created between the suspension, steering, wheels and the frame of the vehicle. When these angles are correct, the vehicle is properly aligned.

Before checking and adjusting any wheel alignments setting, it is good practice to check the suspension and vehicle ride height . Any bent or broken suspension component will mean that setting alignment will be at best difficult and at worst pointless.

The main reasons for correct alignment are to
ensure that the vehicle achieves:
minimum rolling friction
maximum tyre mileage
stability on the road
steering control for the driver.

Diagnosing incorrect alignments is usually just a matter of examining the:
● tyres for unusual wear
● wheels for damage
● steering wheel for position.

Four basic wheel settings or angles determine whether a vehicle is properly aligned.
● Camber is the inward or outward tilt of a wheel compared to a vertical line. If the camber is out of adjustment, it will cause tyre wear on one side of the tyre’s tread. Of the alignment settings camber will have the largest effect on tyre noise
● Caster is the degree that the car’s steering axis is tilted forward or backward from the vertical as viewed from the side of the car. If the caster is out of adjustment, it can cause problems with self-centring and wander. Caster has little effect on tyre wear.
● Toe refers to the directions in which two wheels point relative to each other. Incorrect toe causes rapid tyre wear to both tyres equally. Toe is the most common adjustment and it is always adjustable on the front wheels and is adjustable on the rear wheels of some cars.
● Offset is the amount that the rear wheels are out of line, or off set, with the front. Ideally, each rear wheel should be exactly in line with the corresponding front wheel.

Even your wheels are aligned, an unbalanced tyre produces vibration as it rotates and easily recognized by the driver. Wheel balances more important to driver comfort than tyre wear.

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