Safe Speed Forums

A front wheel blowout typically results in the car ploughing along in a vaguely straight line, with the remaining inflated front wheel still allowing a reasonable amount of steering input; thus you can usually drift over and stop in the side of the road without too much drama.

A rear blowout reduces the grip at the back of the car and at the same time produces a lateral imbalance due to the increased drag of the deflated tyre, thus the car wants to spin and has little means with which to prevent it. In theory you can counter steer to correct it, but with the rear all out of kilter there is little to hold the car stable when you get it straight again and it is liable to go into a pendulum effect of increasing oscillations until it finally breaks awaty. Braking may worsen the situation by unweighting the rear of the car and reducing rear grip even further, though there is a school of thought that your first reaction to a rear blow-out should be to stand on the brakes so that both rear tyres are significantly unloaded and the effects of lateral imbalance reduced.

A classic demonstration of the effect of a rear blowout is the dramatic footage of Nigel Mansell in Monaco in 1986 (I think) when his rear tyre punctured. You see that the rear of the car swings dramatically and he has to constantly apply massive steering corrections right down to a standstill. Only a driver with massive talent and skill could reasonably expect to keep that under control.

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http://www.youtube.com/watch?v=cUWJrBm3L2k

Thats in a straight line. The speed is high but I don't think you'd have much more control doing 70mph.

http://www.youtube.com/watch?v=pUtNNBfJVVQ

At least when the front tyre goes, you have a fighting chance of controlling the car - its just going to understeer. Violently, I'll admit - but if the rear keeps traction, you can control the direction of the car.

I've seen video footage of both instances, I'm sure it was in 5th Gear ages ago. Cornering, if the front tyre goes, you just understeer and head off to the outside of the bend. If the rear tyre goes, the back end swings around violently and you lose all control.

I've had the experience of immediate deflation on two backs and one front (three separate incidents). All happed at approx 69.9999 mph. The front was by far and away the least eventful.

Thanks all,

Just to go completely off-topic for a minute, I can't view the "Youtube" clips. I get the message:

"Hello, you either have JavaScript turned off or an old version of Macromedia's Flash Player. Get the latest flash player. "

Now I've tried downloading the latest Flash Player and that hasn't fixed it. so I guess I must have turned "Javascript" off (whatever that is)!

Does anyone know how I turn it back on again? What is it anyway???

Cheers!

Was shocked at my last set of tyres (fronts only) having been replaced at 20,500 miles (mostley m-way), was told that the Michelin Exalto was a soft tyre so did wear badly. Having said that they are the only Michelin I've liked.

Kwik Fit did the fitting, didn't balance the wheels right so it vibrated and twitched horribly, Citroen sorted it at it's service, was told by my local Citroen dealer that they are charging a premium on any work to company cars wheels & tyres that KF have botched as they are getting so many just lately.

The two main faults they get on a regular basis from KF are poor balancing on C3 & C4 wheels and locking wheel nuts being airgunned on so tightly that they are broken.

Nothing like a KF fitter!!

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http://www.wildcrafts.co.uk

F***ing locking wheel nuts. I tried to get mine off (oh, on a C3) and they... well locked.
I was told by the tyre fitters who I took the car to to get them removed that the C3 wheels are difficult to balance because they don't have centres...? Or something like that. I haven't paid much attention to how wheels attach.
This is how the car came from the Citroën dealer, with the rear tyres going the wrong way, so they obviously didn't pay much attention.

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Andrew.

My dealer told me that the centreless wheels a la C3 & C4 have an adapter for the balancing machine, apparently it isn't always used...

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Gordon Brown saying I got the country into it's current economic mess so I'll get us out of it is the same as Bomber Harris nipping over to Dresden and offering to repair a few windows.

Chaos, panic and disorder - my work here is done.

http://www.wildcrafts.co.uk