Volkswagen Golf Service & Repair Manual: Undulations

Volkswagen Golf Service & Repair Manual / Wheels and Tyres Guide - General Information / Evaluating tyres / Undulations

Radial depressions are slight concavities in the tyre sidewall.

They run from the bead towards the shoulder of the tyre. These parts appear in the figure → Fig..

The cause is the accumulation of material at the joints of the tyre components.

Undulations have no effect on:

Safety,

Service life,

Handling or

Other characteristics of the tyre.

Undulations are visible to varying extents. It is not necessary to inspect the tyre or remove it from the rim.

What causes undulations?

Modern steel belted tyres are constructed with single-ply side walls to save weight.

The sidewall components consist of long strips before they are joined together to form a tyre. They must overlap at the joints. Consequently, slight irregularities or waves are created in the area of the overlapping parts. The overlaps are easier to see from the outside due to the single-ply construction.

Saw-tooth wear

Flat spots caused by storage or handling

What is a flat spot? The terms flat area and flats are also used for the term flat spot. Flat spots caused by storage or handl ...

Flat spots caused by hard braking

This type of flat spots may be caused by hard braking on a rough surface such as a tarmac road. During this type of braking manoeuv ...

Other materials:

Preparatory measures for calibration
Extensive preliminary work is required before the actual calibration can be carried out using → Vehicle diagnostic tester. Prerequisites: Position vehicle on a firm and level surface. ...

Notes on safety
Safety precautions during a road test using test and measuring equipment Observe the following if test and measuring equipment is required during a road test: Risk of accidents due to distraction and inadequate securing ...

Removing and installing speed sensor on rear axle -G44-/-G46-, vehicles with four-wheel drive
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