Run Flat tyres have been constructed specifically for the purpose of remaining functional, for a limited amount of time, when there is no air pressure in the tyre. The use of TPMS (tyre pressure monitoring system) is essential in the use of run flat tyres. As this will alert drivers to any problems.
In the event of a puncture whilst driving, a run flat tyre can still be driven on for around fifty miles - giving you time to drive home, or to a nearby garage safely.
It is possible to switch from conventional tyres to run flat tyres, however, in doing so you need to ensure your car is fitted with a compatible tyre pressure monitoring system. This is essential in relaying to the motorist if the tyre suffers a puncture.
You tell whether a tyre is a run flat tyre by checking the sidewall - unfortunately there is no industry standard code to represent this.
Different manufacturers use different symbols. These include: • Continental Run Flat Tyres – SSR • Dunlop Run Flat Tyres – DSST or ROF • Goodyear Run Flat Tyres – ROF or EMT • Bridgestone Run Flat Tyres - ROF or RFT or RSC • Michelin Run Flat Tyres – ZP • Hankook Run Flat Tyres – HRS or have B at the end of the product number (e.g. K115B) • Pirelli Run Flat Tyres – RSC • Yokohama Run Flat Tyres – ZPS
To ensure you can select the right type of tyre, Blackcircles.com has the word 'Run Flat' listed against run flat tyres on our tyre search results section. So you can easily which products are run flat tyres.
In the majority of designs, a Run Flat tyre is able to remain functional with no air pressure thanks to a reinforced sidewall.
Standard tyres are supported and remain usable due to the air pressure within the tyres. Once this is lost, the tyre will fail.
The reinforced sidewall of a Run Flat tyre can support the car, minus the air pressure, temporarily.
Yes. A very important component required to ensure the accurate use of Run flat tyres is a tyre pressure monitoring system (TPMS).
Due to the fact that a Run Flat tyre can run on zero air pressure, it means that without a TPMS, a motorist may not know they’ve suffered a puncture.
With the TPMS, an alert is flashed up on their console letting them know that they have suffered a puncture and that they will need to replace the tyre as soon as possible.
Yes, in most cases it is possible to switch from conventional tyres to run flat tyres. However, it is important to ensure that your car is fitted with a compatible tyre pressure monitoring system.
As mentioned above - this is essential in alerting you if your tyre(s) suffers a puncture.
Generally, no. Once it has suffered a puncture and been driven on, the structure of the tyre will be weakened.
For this reason, it is dangerous to try and estimate how long it further last. It is always better to be safe than sorry with your tyres.
As with all tyres, regardless whether they are Run Flat or standard, it is important to make sure you look after them - and make regular tyre safety checks. To reduced the risk of them failing.
This is also the case for tyre with nails in them. Unfortunately it is not recommended to fix run flat tyres with a nail in it, due to the potential internal damage which may have been caused.
There is no clear cut answer to this question, as deciding whether or not run flat tyres ‘are worth it’ comes down to individual perspective and circumstance.
There are several advantages to running on run flat tyres – these include the significantly reduced risk of losing control of your car after a sudden puncture, more space in your boot due to the fact you will not need a spare wheel, and the fact you can continue to drive in the event of a puncture for up to 50 miles (giving you time to find a mechanic).
The disadvantages of a run flat tyre can include a higher price per tyre on average, come compared to standard tyres. They are also slightly heavier, as a rule of thumb. People who drive on run flat tyres, sometimes remark on the reduced comfort levels, as the rigid structure of a run flat tyre can cause the driver to feel more of the road.
So, for each person trying to decide whether to buy run flat tyres, there are several factors to consider on each side of the argument.
The benefits of a run flat tyre can come in several different forms.
Most notably, the major benefit is the fact that in the case of a sudden loss of pressure or puncture – a run flat tyre can continue to function for around 50 miles. It is recommended that you do not exceed 50mph once this has happened.
This is a major safety advantage, as not only are you able to remain in control of your vehicle. But you do not need to pull over onto a hard shoulder – for example – and wait for a repair vehicle to collect you.
Another advantage of run flat tyres is the fact that you will have more room in your boot. Given the nature of run flat tyres, you will no longer need to carry a spare wheel in case of a puncture. Saving you room and reducing the weight of the vehicle.
Some of the disadvantages of a run flat tyre can include a higher price per tyre on average, when compared to standard tyres.
Due to the construction of run flat tyres, they also tend to be slightly heavier, as a rule of thumb.
People who drive on run flat tyres will sometimes that they deliver a reduced comfort level - as the rigid structure of a run flat tyre can lead to a bumpier ride, as well as greater cabin noise.
As with all tyres, it is not possible to give a definitive answer on the lifespan of run flat tyres - as a group or category. There are many factors which can affect how quickly a tyre will wear. Such as the type of roads or terrain driven on, the regularity of air pressure maintenance, the overall level of usage, plus much more.
The materials and construction of different models of run flat tyres will also influence how long a run flat tyre will last.
If a vehicle has been developed and fitted with Run Flat as original equipment you should seek some expert advice on whether changing from run flat tyres to standard tyres is advisable. There are a few negative effects of changing tyre types – such as reduced handling performance.
Your suspension will also have been designed to perform alongside the harder riding run flat tyres, so this may need changes to it’s set up to deliver a comfortable ride.
Consult with the manufacturer before making changes of this type.
Most manufacturers will recommend that a run flat tyre, once punctured, should only be driven on for a maximum of 50miles – and should not exceed 50mph when driving.
However, as this may vary depending on the manufacturer and the model of run flat tyre, it is recommended that you check on the specific information given about the run flat tyre you own, or are planning to buy.
Although some car manufacturers are more well-known for choosing run flat tyres to be fitted to their vehicles, you will need to check any particular vehicle you have or are interested in – as many manufacturers will fit run flat tyres on one model, but not onto others.
Audi, BMW, Mercedes and Mini are manufacturers that will commonly use run flat tyres on their models. But there are some others – such as certain Volkswagen cars.
If in doubt, check with the manufacturer of your vehicle.
Given the nature of run flat tyres, it can be difficult to tell when they have been punctured. As such, run flat tyres are required to work with a TPMS (tyre pressure monitoring system). In the event of a sudden, or greatly increased, loss of air pressure this monitoring system will alert the driver.
If the TPMS comes on when driving, and alerts to a loss in air pressure in your tyre(s), ensure that you have the tyre(s) checked by an expert as soon as you can.
Do not reset the TPMS until the air pressure has been restored to the correct level, as this will result in incorrect readings – which could lead to an accident.
An increase in road noise is a common complaint for those who fit run flat tyres. Given the carcass construction of run flat tyres, and their rigid sidewalls, there is an increase in the level of vibrations. Which in turn can cause cabin noise to increase.
Aware of this issue, manufacturers of run flat tyres are constantly looking to improve the comfort levels of their tyres – including reducing the noise levels. The use of noise dampening technology is becoming more common in the latest generation of run flat tyres.
Generally, no. Despite their more rigid construction and specific functionality to carry on performing in the event of a puncture, the materials and compound used in run flat tyres does not differ greatly from those of a standard tyre. As such they will wear at around the same rate – and tyre care, including air pressure maintenance is just as important in ensuring the tyres perform to their full potential.