Tyre Damage

Tread detachment

Local or general separation of the tread from the casing is often caused by overheating of the tyre. Overheating is mainly caused by driving with insufficient inflation and incorrect type tyres for the condition of use.

Air pockets

Infiltration of inflating air through the rubber is commonly due to incorrect repair procedures and the perforation of the airtight lining of a tubeless tyre caused by the misuse of tyre levers during fitting, accidental perforation in service or repair buffing of the tubeless liner not being restored to its airtight state.

These perforations allow air to penetrate as far as the casing cords which then channel it to the ends of the turn-ups of the plies. The air accumulates and causes separation which is characterised by small blisters or cracks.

Once air becomes trapped in a tyre the following occurs: as the tyre temperature increases under normal service conditions, so does the temperature of the trapped air. This heated trapped air expands and gradually forces the separation, thus allowing more air into the cavity, which in turn will also expand and cause further separation.

Sidewall cuts

This may not necessarily have an immediate consequence but it could gradually extend and develop into a rupture of the sidewall. Have all cuts repaired to avoid worsening of the damage.

Rupture of the sidewall

This type of rupture may be caused by under-inflating, overloading, airpockets or an an impact.

Rupture resulting from a cut in the tread

A cut in the tread, which may or may not have affected the crown or casing plies, weakens that area of the tyre. The penetration of grit and moisture into the cut will gradually extend the damage, as will the flexing of the tyre in service, leading possibly to rupture of the plies.

This rupture may not occur until long after the cut and can cause sudden deflation. A cut in the tread is not always easily seen, but can sometimes be detected by excessive wear in the damaged area.

Impact ruptures

When a tyre strikes an obstacle, the casing becomes badly distorted and this may lead to a rupture of the plies. The effects of the shock may not be noticed immediately and also the tyre may not be marked or bruised. More often the immediate effect is localised rupture of only some plies, possibly without external evidence.

Repeated flexing of the casing gradually extends the damage which will eventually appear externally.

Pinch rupture caused by road shock

In such cases the tyre pinched, between the obstruction and the rim. This can result in ruptures of the plies without any immediate visible damage. This damage could occur later in service, showing itself as a sidewall bulge or even a sudden deflation.

Bead damage

Usually due to overloading, under-inflation or incorrect fitting. These factors impose excessive strain which can lead to splitting and separation in the bead area. Damage such as the unwrapping of the casing ply from around the bead core and rupture of the casing in the bead area can be caused. Similar damage can also be caused by excessive heat from brake drums.Excessive flexing of an incorrectly fitted, overloaded or under-inflated tyre can cause the beads to chafe against the rim flange.

Incorrect fitting or removal:

Incorrect use, or positioning, of tyre levers unsuitable for the tyre can cause damage in the area of the bead toe in particular. This in turn could cause air leaks in the case of a tubeless tyre or damage to a tube in a tube type tyre.

Due to overinflation:

Excessive inflation pressure, just like fitting a tyre on the incorrect size rim, can also cause the bead core to break.