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CapriRacer knows what he knows and he seams to be very knowledgeable in his area of expertise, but so far he couldn't bring and ounce of evidence that driving on 5-10 PSI over the sidewall max. could cause the tire to burst.
Radial tire technology, nowadays encapsulates individual cables of material, bands of steel and synthetic fiber rather than layers of fabric or steel, thus in a tire we have more individual components than in a car engine. So without a proper physical test the experts have an almost impossible task of accurately measuring the basic components, much less figuring out which compounds evolved into what.
Tire engineers can only predict how all the compounds; polymers, sulfur, carbon black, oils, waxes, resins will interact with the structural components. I suspect, but I might be wrong, so please CapriRacer correct me if so, that long after leaving the production lane, the tire will evolve and develop new properties, especially if the tire is overheated.
Unless a physical test, lab or road test would be absolutely impossible to predict in any driving conditions at any pressure (PSI). When I expressed this view, CapriRacer said:
(I quote) "Since you haven't got the fundamentals right, what makes you think you've got a good grip on anything else? Especially when you are talking about areas outside the envelope. I've explained why the burst pressure is not something that has value - except as confirmation that the theory works - and it does. As I pointed out, the company I work for doesn't even do burst testing anymore. They are confident they have a good handle on strength calculation and its affect on fatigue."
When does the overheating occurs? When the tire is underinflated. We will need a tire specialist to come with a complete scientific explanation and mathematical equation and create a mathematical model in order to let us how and why tire overheating occurs, but the common sense and driving experience (and in not so many words) says that overheating occurs (chiefly) due to and increased sidewall flexing.
As a visual example, pull out from your wallet a bank or credit card. Put the card on tall between your thumb and the index (or middle finger) and start to apply pressure.
You will see the card will bend very, very easily. That is more or less what is going on with an underinflated tire.
Do that few thousand times and the card will undoubtedly brake due to a chemical deterioration of the plastic on the bending line.
Now, take the card and places it between the fingers on wide. You will immediately see that you will need to apply much more force in order to bend it, and the bending curve will be much, much smaller. That is (more or less) how a properly inflate (45-50 PSI) tire will behave.
A 45-50 PSI tire inflation can have many names. Some of us will call it properly inflated, some might call it hyper-inflated. The tire industry love to call that grossly and dangerously overinflated.
According to FARS, between 35-38,000 people get killed in traffic crashes and other 5 million are getting hurt in US alone year after year after year, for the past 15 years. MVAs in the USA, Road Traffic Accidents and FARS statistics reveals that over 95% of motor vehicle accidents are caused by driver behavior. Driver distracted by a cell phone call or a spilled cup of coffee, under the influence, inattentiveness, running red lights, falling asleep.etc, etc, etc.
The next most common cause is equipment failure such as loss of brakes, and steering/suspension failure. The least common cause for a equipment failure is tire failures.
All reported equipment failure accounts for less than 5% of all motor vehicle accidents.
The most common tire failure is thread separation caused by uneven or worn-out tires caused by improperly balanced tires, or misaligned or broken suspensions.
On the tire failure list, overinflation is yet to be cited as a sole contributive cause of a car crash.
Maybe someone (CapriRacer?) can point out a statistic in regards to the overinflated tires as a cause of failure.
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