Basically advantages and disadvantages of using Run Flat tyres.
We check why there is so many tyre manufacturers producing Run Flat tyres and why there are situations that we should avoid using them or at least be aware of their bad points.
Let’s start with positive factors of using Run Flat tyres
Just imagine you have no spare wheel in the boot, you don’t even have a repair kit and you are in a hurry to work and … you got a flat tyre. It’s something that nobody wants to experience, but does it have to be this way? The solution can be using Run Flat tyres. What is this and can you fit them on any car?
Run-Flat tyres allow you to travel even after a tyre is flat. Generally speaking, after it is damaged, you can travel up to 50 miles distance on a puncture at a speed no more than 50 mph. Currently, this type of tyre is produced by most of the most popular tyre manufacturers. The information of this type of tyre can be found on its side.
Unfortunately, the naming in this case is not universal. Depending on the manufacturer, we can come across different markings and so Run-Flat can be described as:
Bridgestone – RFT or RSC
Continental – SSR or CSR
Dunlop – DSST or ROF
Firestone – RFT
Goodyear – EMT or ROF
Michelin – ZP
Pirelli – RFT or RSC
Yokohama – Run Flat or ZPS
Hankook – HRS
Kumho – XRP
You need to remember that Run Flat tyres are not for everyone. They cannot be mounted on a regular rims. A suitable rim for these tyres are with specially raised hump where the tyre sits, which, in combination with a reinforced bead, ensures that the tyre stays on the rim in case of damage. This rim has the designation EH2 + (Extended Hump). Many manufacturers strongly advise not mounting tyres of this type on standard rims, because these tires do not guarantee their stability after a puncture. We should also remember that the car should be equipped with a tyre pressure sensor system (called TPMS). What other restrictions do Run Flat tyres have?
For the safety of users, many manufacturers do not recommend repairing Run Flat tyres. While a normal tyre could be repaired at a garage, Run Flat tyres are not eligible for repair in most cases. Why..?
Well, Run Flat tyre after driving for several miles is heated and gets damaged so there is a risk of this tyre slipping from the rim, which may cause an accident. As you can guess, the Run Flat tyre, on which we drive without air or only with a reduced air pressure due to puncture, wears quickly. The more you drive on Run Flat tyre with no air, the less chances it can be repaired and more likely you will end up buying new one, which…is another disadvantage…They’re more expensive than standard tyres. They’re also noiser in most cases and harder to get them part worns.
Another problem with Run Flat tyres is that because their walls are much harder hence they put more pressure on the rims and may cause the rims to crack if you hit a pothole so with them on being low profile…definitely avoid high curbs and potholes.
So basically I only found one positive reason why we should use Run Flat tyres but actually it is necessary to use them if they were originally fitted to the car simply because of missing spare wheel. You just need to remember to use TPMS sensors that come with them originally (BMW, Mercedes). Lack of appropriate sensors will reduce a sense of fitting Run Flat tyres as you will simply don’t know what’s the current pressure on each wheel, however it still should notify you if you have lost pressure in one of the 4 tyres.
To summarise I personally fitted my car with non Run Flats and gone with higher profile tyres than advised by a car manufacturer and I’m happy with a ride but for longer journeys, i.e across Europe, I’d go with Run Flat tyres for piece of mind.