Tyre Bulge: Is it Safe and How Can I Fix It?
Main load of the vehicle during driving is distributed on tyres, which transmit it to the road surface and are responsible for traction. Therefore, the tyres are most at risk of the appearance of deformations. Many of them negatively affect the car performance, increase the hazard level and require urgent measures.
A bulge in the tyre is one of the most common damages. It is a change in the shape of the tyre in the form of a swelling in any part of its lateral surface. Such deformation appears gradually and is almost invisible at the initial stage. As you drive on damaged tyres, the bulge increases and becomes visible to the naked eye, which points out the need to take action.
How Bulges in Tyres Occur
To understand how bulges in tyres occur, one should firstly refer to the standard construction of the tyre. It consists of the following parts:
- Beads. They are responsible for the secure fit of the tyre on the disk and its tight mounting on the rim. In a C-shaped cross section of the tyre the beads are the peaks.
- Cord carcass. Cord is the basis of the tyre, consisting of rubberized layers of threads. They cover the entire area of the carcass and are interwoven in a radial or diagonal direction.
- Sidewall – the side parts of the carcass, preventing it from damage and protecting it against moisture.
- Tread. This is an external working part that provides gripping. The tyre tread is a massive layer of rubber with a whole system of grooves.
The occurrence of a bulge in tyre is connected with the condition of the cord, which plays the role of a reinforcing element. Today, most tyres have a radial cord, as it provides better performance.
But when it comes to bulges, the type of cord is not as important as its integrity. If it is damaged, then the internal pressure of the tyre creates a protrusion on its surface. Rubber stretches as the air seeks the weak spot to come out. If the car owner continues to drive on such tyres, the bulge continues to increase, which can lead to tyre burst.
What Causes a Tyre Bulge
The immediate causes of the cord damage, which lead to the occurrence of a bulge, include:
- frequent driving up a kerb when parking;
- hitting potholes in the road;
- manufacturing defect;
- car accident.
The most common reason of bulge occurrence is considered to be hitting potholes, especially at high speed. Overcoming an obstacle, the tyre itself may withstand a strong impact, but this does not guarantee that the cord will not break inside.
The most vulnerable to the occurrence of a bulge are poorly inflated tyres. If the car owner does not check and maintain the recommended tyre inflation pressure, there is a risk of protrusion occurrence.
Is it Safe to Drive with Tyre Bulge
Having discovered a bulge in a tyre, a driver would first wonder if it is safe to drive on tyres with such damage. Experts do not recommend it. At a low speed problems may not arise, but at high speed unpleasant consequences are possible. Of particular danger are bulges on the front axle, and there are several reasons for this:
- wheel runout causing unbalance;
- worse steerability or even complete loss of control;
- severe tyre overheating and reduced traction.
In addition to danger, driving on tyre with bulge leads to premature wear of wheel bearings, loosening of the car suspension, damage to shock absorbers and ball bearings. When the impact increases, the tyre can simply burst, which can be caused by:
- hitting a pothole on the road with a damaged tyre;
- very high driving speed;
- abrupt start or braking;
- maximum load of the car.
Recommendations in Case of Finding Yourself with Bulge in the Tyre upon the Road
- You should drive carefully and not long, at speed up to 70 km/h, without extreme manoeuvres and braking, which could provoke tyre bursting.
- The car itself should be unloaded to the maximum, for example, passengers should change from the car to public transport.
- Tyre inflation pressure shall be reduced by 10-15%.
- You should carefully monitor the condition of the road when driving to avoid hitting pits and potholes.
How to Fix a Tyre Bulge
- Installation of internal reinforced patch. This procedure does not give a one hundred percent guarantee that the defect will not increase, but somewhat extends the tyre life.
- Sewing the damaged area with kapron threads, followed by vulcanization with reinforced rubber.
- Fitting of inner tube.