I have only had one blowout, it was years ago in a Ford Cortina and was caused by a small sharp rectangle of metal being thrown up by the offside front wheel and going on to slice through the sidewall of the rear offside: Bang!
I have heard of many blow-outs and often there is an obvious cause, as in my case above, but in a worryingly large number of instances, there seems to be no obvious precursor to the tyre failing.
So my question is, why do these tyres blowout?
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never had a blow out myself, but I understand that many blowouts are due to under inflated tyres overheating.
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......... why do these tyres blowout?
I imagine there could be various possible causes. I had a rear tyre sidewall split at a moderate speed and at a small mileage, and I put it down to the previous owner having either kerbed it or run over something large and hard. The leak was fairly moderate and the only reason I knew there was something wrong was the car started to pull slightly to one side. Nothing dramatic at all.
Edited by L'escargot on 04/09/2008 at 10:43
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I never buy second hand tyres or those from breakers yards because you have no idea how the unit has been treated before you got it.
Blow outs also happen because people don't check for damage and drive on tyres with huge egg like growths on the tyre walls and cuts so deep in them you can see the ply structure underneath.
Kerbing of the tyres is the usual cause of tyre wall damage.
Deep cuts to the tread or any area really do need investigating further and if you can pull the tread back enough to see the ply underneath - the tyre has had it. Any cuts more than 1 to 2mm deep on the tyre wall, as personal preference, I will not use that tyre.
Driving long distances on an over or underinflated tyre may also cause blowouts too. Old tyres that are cracking - these need replacing and this is an MOT fail too!
Remoulds are notorious for blowing (firstly having usually thrown the tread all over the place) out and it is why you see so many commercial vehicles having them as it is cheaper (a lot too) to buy a commercial remoulded tyre than a new one.
Very rare for a new tyre to blow out unless there is 'user damage' firstky involved to start to cause the breakdown of the integrity and structure of the unit itself.
Edited by Tron on 04/09/2008 at 10:42
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>>I never buy second hand tyres or those from breakers yards because you have no idea how the unit has been treated before you got it.
What do you do when you buy a second hand car?
Over inflated tyres, unless seriously so, aren't a problem. Under inflation, on the other hand is really quite dangerous. As the tyre flexes more, it overheats - quickly!, there's no long distance to be had once the tyre is seriously low on pressure. Most cases of commercial tyres losing their tread capping is just overheating due to low pressure - typically, a gradual leak which had gone unchecked, and un-rectified.
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many commercial vehicles having them as it is cheaper (a lot too) to buy a commercial remoulded tyre than a new one.
Commercial tyres can have the treads recut, too.
Car remoulds are cheaper than new tyres, also.
Using remoulds saves on carbon emissions.
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I've had a couple of incidents like this, one of which was caused (I'm pretty sure) by debris picked up on the docks at Calais, during the remodelling in the 1990s. When we came safely to a stop on the side of the A2 the tyre had several clout nails in it. I think one of them had been holding the air in until the wheel started spinning at motorway speeds, at which point it came out. This is why people who say '90mph on an empty motorway is perfectly safe' are deluding themselves.
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>>is perfectly safe
Anyone who say *anything* is perfectly safe is deluding themselves.
90 mph on an empty motorway,...., ahem autobahn, is a risk I'm happy to take.
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90 mph on an empty motorway .... ahem autobahn is a risk I'm happy to take.
Well, we'll have to disagree on that then. This particular incident was rather, um, exciting (yes, that's the word) at 65. It's likely we would have rolled if we'd been going much faster.
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>>Well, we'll have to disagree on that then.
Getting into a car at all is risky. Some idiot can run into you while you're parked at the traffic lights and cause serious damage to you. It's a question of where to draw the line.
For me, the probability that there's going to be a life threatening problem on an empty motorway at 90 mph is much less than on a packed motorway at 70.
Taking your tyre example, on an empty motorway, there are only 4 tyres, my tyres, which I keep in tip-top condition, which could fail and cause me harm. On a busy motorway, there are hundreds of tyres, in who knows what sort of condition, which could fail, and lead me into a potentially harmful accident.
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Taking your tyre example on an empty motorway there are only 4 tyres my tyres which I keep in tip-top condition which could fail and cause me harm. On a busy motorway there are hundreds of tyres in who knows what sort of condition which could fail and lead me into a potentially harmful accident.
The other factor is that on the empty motor way you have some level of control over mitigating the risk. I.e. you can check that your tyres are in tip top condition, where as you have no control over the others.
For me risk taking is about understanding and having sone level of control of the risk.
Life is full of risks, even eating a bag of peanuts can be deadly...
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What triggered me to start this thread were the assertions of a few motorcaravan drivers who say that they have had blowouts with no obvious cause.
Motorcaravans are quite heavy beasts (basicly laden commercial vehicles) and ususally only do a small annual mileage. These drivers complaining about blowouts are adament that their tyres were correctly inflated, not kerbed, bought new, not overloaded and not driven too fast (difficult to do in a motorcaravan anyway).
One or two such claims could be dismissed, but a whole group should (must?) have more weight attached to it. So what is causing these tyres to fail? Is it a manufacturer's fault (the state of these tyres post-blowout makes examination very difficult).
Any ideas?
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Motor caravans are often heavily loaded (close to the maximum gvw in many cases). Also, a lot of such vehicles are only used every few weeks, leaving the opportunity for flat spots or uv cracking to develop while parked.
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It's a very long time since I last bought a new tyre.
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Motorcaravans as you say are often fully loaded and they (and large caravans) often run at or near to maximum tyre pressure. This shortens the life of the tyre, but since they don't do many miles the tyre often looks 'like new'.
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Any ideas?
Cheap tyres, combined with the rhythmic side to side swaying of the caravan?
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Life is full of risks ...
Profound, man, really profound.
But why add to them unnecessarily? Driving at 90mph on the motorway:
a) isn't particularly exciting or even especially interesting
b) isn't much of a challenge, even in my car, though it would take a while to get there
c) doesn't make you more attractive to women (or men)
d) is more risky, but more importantly more perilous in the event of a tyre failure or similar
Given the lack of real benefits, I choose to control the levels of risk and peril by not driving at 90 (the thrill alone might make 180mph worth the risk). The reason is that I have had two sudden tyre failures in my relatively short driving career that would probably have had serious consequences had I been doing so. I am fastidious about checking and replacing tyres and always have been, but a tyre can be perfect at the start of a journey and pick up damage along the way, or can appear perfect but not be. We disagree, so whoop de doo. Drive carefully and good luck.
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In all my years of driving and in the motor trade I've heard only two proper blowouts, (Exploding tyre).
The first one, back in the 70's happened when a fellow mechanic was inflating a Mini spare tyre, there was a loud bang - the tyre bead had blown over the rim.
The second was a couple of years ago, an almighty bang, rattled doors and windows for hundreds of yard, it was a bus tyre, parked in the depot next to my workplace after a motorway run.
Back in the 70's (again) a young lady came into the workshop complaining that she'd pumped her tyres up with the free air, and they still looked flat. The Michelin X ' s on her BMC 1100 were at 80psi. No explosion though - but I was a bit apprehensive whilst deflating them.
More recently I witnessed a Transit van clip the kerb on a bend. I watched the n/s/f tyre go down as he passed me, and heard the hissing, no bang though !
I guess that most 'blowouts' are ordinary punctures and the driver just keeps going until he's forced to stop with a shredded tyre, then it's a blowout.
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I was bimbling along on the autobahn somewhere in NW Germany at about 65 (as I do) and was passed by (I think) an Astra or equivalent doing 80+. When he was about 100yds ahead his offside rear exploded visibly and audibly. Luckily it didn't seem to send the car off course, or he controlled it well. A bit worrying though.
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They hardly ever do. Tyres are amazing bits of kit these days......have you noticed that a run-of-the-mill airbus containing tons of people, luggage and fuel has only two more than your car? And they get banged onto concrete from a great height several times a day!
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......have you noticed that a run-of-the-mill airbus containing tons of people luggage and fuel has only two more than your car? And they get banged onto concrete from a great height several times a day!
Loads of info here about aircraft tyres ............ tinyurl.com/5s3vbg
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L'escargot that was interesting reading - I'm into aviation stuff too and that was a welcome change from the usual motoring stuff!
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I'm into aviation stuff too and that was a welcome change from the usual motoring stuff!
IIRC radials were developed for Concorde after the Paris accident.
Other aircraft operators / makers then wanted radials made in other sizes for beasts.
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Many thanks, M. l'Escargot......most interesting. This really is a wonderful site for info. I assume your airbus/plane tyres cost more than the £80 each i have just paid for my roadcar!
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About 25 years ago I had a O/S rear tyre blow in a Range Rover at 90ish MPH on a motorway - It had had new Michellin tyres (and tubes in those days) fitted about 400 miles before - I gently slowed and pulled over onto the hard shoulder - when I stopped the tyre was burning - changing it in the dark by the side of the road was not a nice experiance (we did things ourselves in those days, before mobile phones) - I sent the old tyre back to Michellin but they said because of its condition they would do and say nothing.
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think&drive
You are echoing my point that there are a number of blowouts that have no obvious explanation and that the tyre is in such a state afterwards as to make determining the cause difficult / impossible. It is these inexplicable events that cause me concern, because there seems to be no way of protecting ourselves from them.
The tyre manufacturers do not seem to be bothering to put any energy in finding out the causes, or even if the cause is their fault.
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I too suffered 2 tyre failures ( or blow outs ) as they exploded & took the wheel liner out as well on 2 seperate occassions but with the same make of tyre. These were 225/45/ZR18 Pirelli's!. Apparently not uncommon!. Mine were not driven up or down kerbs etc & just gave out at speed each time on a motorway. Impossible to tell wether they had struck a sharp object or not although I was alway's fairly observant .
The only possible common factor is I used to wash my car with a steam cleaner ( yes hot ) with particular attention to the wheels to remove the brake dust. I have since read an article that using a pressure washer on tyres can cause the rubber to delaminate! with the possible risk of tyre failure!.
no more pressure washing around the tyres for me & no more blow outs since iether!
I Doc
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