At what speed do punctures become catastrophic?

londonTiger

IO've had two punctures which were either caused at the time of the incident or were slow punctures (I am not 100% sure).

Both times I didn't lose control of the vehicle, the car just because really sluggish on the side of the puncture. Car veered towards that side. First one I was driving 30mph, second one I was driving 45mph.

Was wondering at what speed would the car completely lose control at the event of the puncture and swerve/tumble skit out onto another lane and cause an accident?

WTFH

It's not so much the car speed as the speed of deflation of the tyre - or speed of disintegration, if you're really unlucky.

Rodney_Trotter

londonTiger wrote: »

IO've had two punctures which were either caused at the time of the incident or were slow punctures (I am not 100% sure).

Both times I didn't lose control of the vehicle, the car just because really sluggish on the side of the puncture. Car veered towards that side. First one I was driving 30mph, second one I was driving 45mph.

Was wondering at what speed would the car completely lose control at the event of the puncture and swerve/tumble skit out onto another lane and cause an accident?

How often do you really check your tyres?

It's not an exact science so to speak as a lgv can lose one at 56 and still pull safely onto the hard shoulder. A blow out at 30 should still allow you to control the vehicle.

brat

It's not so much the speed, but how the car and you react. If you keep calm and don't do too much with the steering the car should allow you to come to a steady stop with no dramas even from high speeds.

tberry6686

Last puncture I had was when I hit a piece of sheet metal lying on the road. Inside wall of the front passenger tyre was ripped through.

Speed was about 70mph and first I knew about it was a bang as the tyre burst. Shakey few moments while I slowed to a stop but never really felt that I was losing control of the car (love the way it handles with only 3 inflated tyres compared to what I would have expected)

forgotmyname

Keeping the steering steady and in a fairly straight line to reduce speed. Its when people overreact and try to do a 90 degree turn and things go badly wrong.

I was watching one of the police shows earlier. Car on the motorway 70 - 80. Police car on its way to an incident and wanted to pass. Driver oblivious to them. Then suddenly must have thought oh S... and swerved to the left. Totally lost it. No need for a puncture.

Richard53

One of the great things about tubeless tyres is that they tend to deflate slowly. Even with a proper puncture (rather than a slow leak) in most cases you get plenty of warning - a howling noise, steering pulling to one side, shuddering etc. The only thing that could cause a blow-out (i.e. total deflation in an instant) is physical damage such as described above. I have driven for 42 years and probably 700,000 miles, and I have never experienced a blow-out. The few punctures I have had have been either slow punctures I have spotted while at home, or gentle deflations that at least allowed me to get home.

It also depends very much on which wheel is affected. I once drove an (old-style) Mini home for 50 miles with a flat rear tyre. It can only have had about 10 psi in. I can honestly say I didn't notice, as the car handled normally. Non-driven wheel, very little weight on it.

Hintza

I've had some fairly punctures in my time and have never felt that I was even coming close to losing control of the car.

epninety

I've been unlucky enough to have two blowouts, in different vehicles, both at motorway speeds.

One was a sporty car with very low profile tyres - once I got stopped, the sidewalls were still there, but the tread band was torn off.I had a slight drone for a mile or so beforehand, but no other warning - suspect I picked up a fairly quick puncture a few miles previously. There was a bang, a twitch of the steering as it pulled hard to one side, and that was it - no great drama.
The second was a tube failure in a large 4x4 tyre - no warning at all - bang, bigger swerve - probably moved half a lane width before I caught it - then off to the hard shoulder.

Both were rear tyres, both were luckily on straight sections of road, but neither really felt like there was a real danger of losing control. I think the real biggie is not to panic and be as gentle as you can with the controls.

marleyboy

There are many factors to take into consideration. I have had a blow out on the motorway and control was easy enough to allow me to reach the hard shoulder.

You would have to take into account, how rapid the deflation is, compounded by the speed of the vehicle, the gradient of the hill, the tightness of the bend,the grip of all the tyres, etc.

Weird_Nev

Generally speaking, it's not the speed you're travelling at, but the rate of deflation that's the problem. That said, speed can be a major factor fora couple of reasons. For one, it can destroy the tyre quickly because of the forces involved, for another, there's more energy to get rid of, and it's going to be harder to control the car at speed.

When a tyre is low on pressure, it flexes much more with each rotation. This causes it to heat up more than a correctly inflated tyre. The heat can weaken it and cause it to fail catastrophically.

Check your tyre pressures before any high speed/long journey. Once you know what they look like a visual check will do (though it can be hard to check with low profile tyres). Running low pressures at high speeds is a recipe for "blow outs", at which point you're struggling to control a car with 3 tyres and one metal rim trying to dig into tarmac.