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

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