The reason of unilateral wear in many cases is style of driving, but sometimes and the wrong adjustment of corners of installation of wheels.

The increased lateral wear

Fig. 4.6 . Example of lateral wear of tires

Lateral wear, more often in a combination to attritions on edges of a protector and thin cuts, arises always when tires work at extremely big coal of lateral withdrawal, and consequently "tinder" on a paving (fig. 4.6) .

Fast driving on sites abounding with turns results in particular on external shoulders of the tire in the increased wear.

The rounded-off external shoulder of the tire together with high degree of wear of external blocks of a protector speaks about fast driving in bends. Such wear turns out because of the corresponding style of driving.

For optimization of rideable qualities the running gear is adjusted on certain parameters of a convergence and disorder of wheels. If tires are maintained at excellent from set conditions, it is necessary to reckon with the unilateral and increased wear.

Especially the RUUK wrong parameters can result in bigger unilateral wear, danger of non-uniform wear besides increases.

Negative convergence

Fig. 4.7 . Convergence of wheels

Distance between wheels in front – A more than B distance behind (the C direction of movement).

Convergence or positive convergence

Fig. 4.8 . Convergence or positive convergence

The distance between wheels in front of A is less, than B distance behind (the C direction of movement).

To avoid unilateral wear of tires, it is necessary watch that corners of installation of wheels always were in limits of the admission of automaker. More often corners of installation of wheels deviate nominal parameters because of external influence, for example rigid contact to a border at a parking.

At RUUK it is possible to define, whether there are corners of installation of wheels within the admission or it is necessary to adjust them.

Changes in a running gear

Use of «a set of the truncated springs» and/or the light-alloy wheels which have not been allowed by VW, can lead to corners of installation of wheels which differ from put by a design.

Even if corners of installation of wheels during RUUK at the motionless car in norm, because of the changed height and the provision of wheels during movement nature of movement of a suspension bracket of wheels can change.

Thus, non-uniform wear is programmed previously.

Wear of the central part of a protector

This nature of wear is shown on driving wheels of cars with powerful engines which often pass long distances at great speed.

At high speeds diameter of the tire at the expense of centrifugal force increases in the middle of a protector more than along the edges. Thereof the motive power is transferred on a road cloth from an average part of a protector. This fact is reflected in turn in nature of wear.

Especially considerably such wear is shown on wide tires.

Air pressure decrease in tires to avoid such wear it will not be possible.

ATTENTION For the safety reasons at all it is not necessary to reduce pressure of air in tires below the ordered.

More or less uniform wear can be reached at the expense of timely shift of wheels from the leader on not driving axis.

The increased wear of a protector

Fig. 4.9 . The increased wear of a protector

Typical picture of wear of the tires established on driving wheels of the car with the powerful engine (fig. 4.9) .

Bigger wear of an average part of a protector of tires is a consequence of the loadings arising because of centrifugal force of the tire and transfer of a motive power on a road cloth.