Run-flat tires are very convenient on paper, allowing you to keep driving even when one is punctured. While you can’t do this indefinitely, it allows you to reach a safer place to change the tire. But how do they work and is there a catch?
There are two main types of run-flat tires: the self-supporting system and support ring system.
The self-supporting tire system relies on the tire’s reinforced sidewalls to support the vehicle in case the tire loses air. These tires will allow you to continue driving at a specified speed over a certain distance. These are determined and specified by the tire’s manufacturer. Meanwhile, for tires using the support ring system, a ring of hard rubber or another structure is built into the tire. When the tire loses air, this ring supports the vehicle’s weight.
Both self-supporting and support ring run-flat tires can only be equipped in vehicles with a tire pressure monitoring system (TPMS). It’s too dangerous to use them without the TPMS because the tires will keep functioning despite a puncture. With no TPMS, you won’t realize the tire is underinflated until it gives out entirely.
Run-flat tires are an excellent tire option, but they also come with some drawbacks you should be aware of. Here are all of the advantages and disadvantages of this style of tire:
The advantages of run-flat tires are mainly linked to their ability to remain usable even with a puncture.
When punctured, a run-flat tire typically allows you to drive safely for up to 50 miles. This lets you find a safe place to change the tire. Instead of having to get out immediately in the rain or snow or in a dangerous area, you can keep driving until you find a suitable location. You might need to drop your speed to reach the maximum distance the tire can travel. It’s best to check the owner’s manual to find the exact details for your particular vehicle and its included run-flat tires.
In case of a blowout, a run-flat tire retains near-normal steering and handling. There’s less tread destabilization and weight transfer thanks to the tire’s nature.
The convenience of a run-flat tire extends beyond its ability to keep going after losing air. Because you don’t need to bring around a spare tire, automakers typically utilize the space for other features such as more interior room or storage space.
There are a few disadvantages that come with run-flat tires, most of which are linked to their construction and use case.
The whole point of having a run-flat tire is that you don’t need to carry around a spare tire. Unfortunately, this isn’t always the best in extreme cases. Sometimes, the 50 miles you can travel with the run-flat just isn’t enough, especially if you don’t notice right away that the tire is losing air.
It can be difficult to notice changes in pressure in a run-flat tire, which makes the situation of an unexpected, sudden blowout that much more likely. For starters, because you can keep driving with a deflated run-flat tire, missing the vehicle’s warnings from the TPMS may lead to the tire giving out unexpectedly. It’s harder to tell if the tire is low on air due to the lack of bulges in the sidewalls.
In addition, just because run-flat tires can keep going with a puncture doesn’t mean blowouts are out of the picture. The tire can disintegrate if you drive beyond the zero-pressure range or over the speed limit. Punctures in the side walls and larger impacts can also lead to needing a tow truck for a full tire replacement.
Using run-flat tires tends to result in harsher rides due to the stiff sidewalls. Ma-nufacturers typically adjust the suspension to account for the stiffness of run-flat tires.
The cost and availability of run-flat tires is also a factor to consider. Run-flat tires are more expensive than regular tires and they’re less common. As a result, if you don’t live in a big city, finding a new run-flat tire if yours is damaged might prove difficult. In addition, run-flat tires can’t be patched, plugged, or repaired, meaning you need to replace the whole tire when it’s damaged.
When it comes to choosing between run-flat tires and regular tires, the choice really depends on what you want to prioritize. Regular tires are more affordable and easier to find on the market. At the same time, they can be repaired and patched. They boast a longer tread life and slightly lighter weight.
At the same time, getting a flat on a regular tire can be a huge pain and a potential hazard depending on where the flat occurs. Run-flat tires have their drawbacks but the benefit of being able to drive a good distance to a safer place might just be worth it.
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