– Symptoms of a flat tyre
– Why does a tyre puncture? Risk factors.
– Is a flat tyre repairable?
– How to repair a tyre?
It is reasonable to expect about 40,000km of life out of the tyres for the tyres’ average set. Considering that the average Aussie drives some 15,000 km each year, the average driver can expect his tyres to last 2-3 years. It is, therefore, not frequent, but it happens.
Is a flat tyre a haunting experience? In any case, a lousy inconvenience that often leads to immobilization and loss of time.
Symptoms of a flat tyre
A puncture can exist if the tyre is flat or not. There are small punctures that cause slow deflation. How to spot a flat tyre?
– The tyre is flat, burst or with a clear cut.
– The tyre is flat, and the cut is not visible: re-inflate the tyre and put the wheel in a basin filled with water to detect the source of the leak.
Pressure sensors indicate a frequent drop in pressure, whereas a tyre is only supposed to lose a 0.1 bar per month naturally.
– The driver feels a loss of handling, and the vehicle pulls to one side.
Why does a tyre puncture? Risk factors.
In the case of a tubeless passenger tyre, as in the case of an inner tube, there are common causes of potential punctures :
– Violent shock with a sharp object: logically, the tyre is not strong enough to withstand all types of aggression. The puncture is instantaneous, and the loss of air is rapid.
– Under-inflation: An under-inflated tyre collapses and loses its strength. Forced by the vehicle’s weight and centrifugal force, the plies of the tyre eventually break, causing a hernia or blowout.
After examination by a specialist, repairing a flat tyre will give it a second life at a lower cost.
This section deals with the repair of a passenger or light truck tyre that has suffered a puncture.
Good to know: tyre professionals issue the rules mentioned below, but there is no law on the subject. The repair of a tyre is binding on the person who carried it out.
Can a flat tyre be repaired?
Before changing a flat tyre, you should check whether it can be repaired. This must be done by a professional who must dismantle the tyre and observe it from the outside and the inside.
– Exterior examination: the sidewalls must not show any puckering traces, and no metal or textile plies must appear.
– Examining the notch: it must be on the tread for speed ratings higher than T and run-flat technologies and no more than 6 mm.
◦ A sidewall can only be repaired with a speed index less than or equal to T and if the cut is 3 mm maximum.
◦ The bead area allowing the attachment to the rim must not be damaged.
– Interior Examination: The inside of the tyre must be new and must not show any puckering called marbling or “tyre powder”, synonymous with a deteriorated tyre.
– Old tyre = replacement. You must replace a tyre with a cracked outer appearance if it is punctured.
A tyre can be repaired several times, although it is not advisable to do so more than twice. For self-supporting sidewalls, only one repair is tolerated, but the tyre then loses the benefit of its run-flat capability.
How to repair a tyre?
When a tyre is repairable, different technologies exist:
– PRPs (Pneumatic Repair Parts), also known as mushrooms, are recommended by professionals. Indeed, they propose a repair from the inside of the tyre, which requires an internal examination and is also a qualitative solution.
– A second solution that is common, but not recommended by some specialists, is plugging “wicks”. It is done from the outside of the tyre.
– Hot” repairs with adapted plasters are qualitative solutions but require specific equipment and are more expensive. This system is, therefore, much rarer.