Punctures and “Run-Flats”
I hope that it’s been raining where you are. We needed it.
However, one side effect that can get us involved, is the greater risk of a puncture.
Why? Because wet rubber cuts easier, and is pierced easier, than dry rubber. When the tread rubber is almost gone, then the incidence of punctures increases markedly. A fair statement is that the rate of punctures doubles when there is only the last ten percent of the tread thickness left.
So it’s only flat at the bottom, you are told by unsympathetic observers, while you struggle with over- tightened wheel nuts, and having to unload the boot to find that long neglected spare wheel. And of course, it’s still raining.
So what do you do about it? An ounce of prevention, and all that.
First- is there a spare wheel in the wheel well. Is there a wheel well? Good question. Many modern cars/SUV’s don’t have a spare. They supply a can of gunk to seal the tyre, and get you home. Supposedly.
This is what is known as a “run flat failure”. The tyre invariably is on a rear wheel, and has been run in a straight line, deflated, at speed for a considerable distance. The sidewall “knuckles under” midwall where the rotating tyre hits the ground, and the heat and distortion actually melts the reinforcing cords in the tyre casing. So after around 10 km, it fails, disastrously. As the driver of this utility explained, “it happened on the freeway, mate”.
You’d need a pretty big can of gunk to fix that, mate!
Then they started the unenviable task of finding a replacement tyre. Being a utility, it was shod with commercial (or L.T.) tyres, which even though it was a Holden, aren’t always carried by retail tyre stores. Took the whole afternoon.
So make sure that your vehicle has a spare, that it’s got air in it, and can be accessed. It doesn’t matter if your new car has a steel wheel, with a different sized tyre on it, when all the rest are spiffy low profiles on mag wheels- it has been matched and approved for rolling diameter ,and load carrying capacity, and it’s legal.
If it’s a used car, make sure that it’s got a spare. Period!