Repair a flat tire

After examination by a specialist, repairing a flat tire will give it a second life, at a lower cost

This part deals with the repair of a passenger car or light truck tire that has been punctured.

Good to know: the rules mentioned below are from tire professionals, but there is no law on the subject. Repairing a tire commits the person who performed it.

Is a flat tire repairable?

Before making a change of flat tire, it must be checked whether it is repairable. This must be done by a professional who must disassemble the tire and observe it outside and inside.

• External examination: the sidewalls must not show any traces of creases and no metallic or textile sheets should appear.
• Examination of the notch: it must be on the tread obligatorily for the speed indices higher than T and the run flat technologies, and of 6 mm maximum.
• A sidewall can be repaired only with a speed index less than or equal to T and if the cutoff is 3 mm maximum.
• The heel area allowing the grip on the rim must not be damaged.
• Inside examination: the inside of the tire must be as new and not have any folds called mottling or “tire powder” synonymous with a damaged tire.
• Old tire = replacement. A tire with a cracked exterior appearance must be replaced in the event of a puncture.

A tire can be repaired several times even if it is not advisable to do it more than twice. For self-supporting flanks, only one repair is tolerated, but the tire loses the benefit of its run flat capability.

How to repair a tire?

When a tire is repairable, different technologies exist:

PRP (Pneumatic Repair Parts), also called mushrooms, are recommended by professionals. Indeed, they propose a repair from the inside of the tire which imposes therefore the internal examination and which is also a qualitative solution.

The “wicks” of capping are a second solution that is common, but not recommended by some specialists. It is done by the outside of the tire.

“Hot” repairs with suitable plasters are qualitative solutions, but which require specific equipment and are more expensive. This system is therefore much rarer.