What is Run-flat Tires?

The Run Flat tires have been around since the 80s, but only now are becoming common as the provision of optional equipment and even standard. However, even if we have heard about it, do you know what a Run Flat tire is? If we are good at English, we will find the clue in his name.

Run Flat tire is one who becomes “flat” (flat) when we had a puncture on the road. That is, it is a tire that can circulate even when the air pressure decreases. AIts usefulness is given by being able to drive several kilometers until you find a workshop or arrive at your home.

As a temporary replacement, they have a speed limit that generally set at 80 kmh and an established distance of around 80 km. In either case, it depends on the manufacturer’s specifications. Some car companies suggest a distance that doubles that number, but tire manufacturers do not.

Warning: never touch a wheel that has punctured because it will heat significantly. Please wait for the tire to cool before handling it.

Run Flat tires

How does a Run Flat tire work?

There are two types of Run Flat tires available in the market, but the idea behind them is the same. In the tire, there is a structure that allows it to maintain its shape even after a partial or total loss of air pressure.

The most common type of Run Flat is one with a reinforced sidewall that prevents the rubber from becoming deformed, allowing it to drive after having suffered a puncture. Then there are others with an internal rubber ring or some other type of support material. This ring sits inside the wheel and helps support the weight of the vehicle if the tire is punctured; essentially, it rests on this structure.

It recommended that Run Fat tires adjusted to a type of tire called EH2 (Extended Hump), which acts as a non-slip block between the metal and the rubber when the tire is at zero inflation pressure. Standard wheels are known as H2, and it is possible to place them with Run Flat tires, but they do not guarantee the same safety standard.

Since still functioning despite losing pressure, all just run-flat tires can use in a vehicle equipped with a control system Tire Pressure (TPMS for its acronym in English Tire Pressure Monitoring System ). The TPMS warns the driver when one of his tires begins to lose air. Without it, you may not distinguish when you are rolling with the flat tire.

Warning: never try to repair a Run Flat tire. It is a sacrifice kit. It designed to travel a limited distance, and not a single tire manufacturer recommends repairing it. You cannot inflate a flat tire once you have suffered a flat tire.


  • You can drive with a flat tire. The main benefit of a Run Flat tire is to be able to circulate without air in the chamber. You don’t have to get out of the car, not because of the rain, or a busy road. As in the world of medicines, read the instructions on this tire, and consult your trusted workshop.
  • Better stability after a blowout. Sudden deflation or perforation can destabilize a car drastically. Because this tire can withstand the weight and momentum of the vehicle without air, the direction and dynamics of the car will not change so drastically.
  • Lower vehicle weight. Without a spare tire and repair tools to replace it, the car’s weight theoretically reduced. However, the weight loss in the trunk compensated by the weight. The gain for each Run Flat tire for its reinforced structure. That said, the removal of the spare wheel allows engineers to reallocate the space for some other purpose, such as increasing the interior space.

Run Flat tires


  • Without replacement. As it increases the useful space of the vehicle, those cars equipped with Run Flat tires do not carry a spare wheel, jack, or tools.
  • They can increase tread wear. A 2013 study by JD Power found that, in North America, people replaced their Run Flat tires an average of 9,500 kilometers earlier than the owners of conventional tires.
  • Manufacturers place a softer compound on the tread to maximize grip and comfort. The side effect of this design results in a shortening of the life of the band. However, currently, there shouldn’t be a marked difference with conventional tires.
  • Blowouts are still possible. If a driver does not heed the dashboard warnings and drives more kilometers than those agreed or above the recommended speed, the tire can begin to disintegrate, with the same destabilizing effects. Also, if the puncture occurred on the sidewall of the tire hit a bulky object, the driver would have to call a crane.
  • It isn’t very easy to say if there is little air. Another side effect of a more rigid construction is that the sidewalls do not widen if the air pressure is low. Therefore, it is essential to have a tire pressure control system and check the pressure frequently. Otherwise, you would never know that you have a flat tire.
  • Price. Run Flat tires are more expensive to replace. Prices will vary according to the type and location of purchase, but it is not uncommon to pay a bill of 90 or more than 100 euros for this type of tire. That without counting the tire.
  • They are heavier and less efficient. Its greater rigidity entails an increase in mass compared to conventional tires, and the average fuel consumption rises between 1 and 2%, both on the road and in the city.

What is the life of a Run Flat tire?

We have just read that, conditioned by the search for comfort and resistance, the tread of a Run Flat tire is more prone to wear than that of its conventional equivalent. That was a fact, until recently. The progress in the development of tires has led to some tires that will differ little from their simpler counterparts.

In general, Run Flat tires use the same rubber compounds as conventional wheels so that you can expect similar longevity. Despite its reinforced components, the tread wears at the same pace as standard tires and requires the same level of care and maintenance. Keeping the wheels at their optimum pressure and checking it off will help increase their life before having to replace them.

Am I worth a Flat Run tire?

The first question that comes to mind is the one that concerns its price. Are they expensive? In a word, yes. Because Run Flat tires are not widely widespread, they tend to be more expensive than normal tires and can only install on certain cars. Combine that with the fact that they can’t repair, and they won’t make much sense to most drivers.

There is no doubt that Run Flat tires are more expensive than conventional tires (from around 90 euros), and it is obvious that they offer a much safer option for circulation. With these shoes mounted on your car, the chances of reducing an accident. Due to a puncture reduced to almost zero, they offer more reaction time to the driver. If the manufacturer allows repair and we are regulars, it can be a good alternative.

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