Imagine this situation on the motorway. You're making good progress (70mph...ish) and suddenly you see brake lights flare in front of you. You realise you need to stop, and fast. You have no ABS. Is it best to:
a) Try and brake progressively up to the point of locking the wheels...
or
b) Push on the brake pedal as hard as you can, both front wheels locked and sliding (in a straight line, hopefully!). Ie, the maximum possible force on the brake pedal.
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Definitely (a) because your braking distance will be less if the wheels do not lock up and just pointlessly slide over the road surface. As soon as the wheels start to lock, you should release the brake momentarily. That's what ABS does - prevent the wheels locking up. Although if you have not left a sufficient gap, nothing will save you!
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Definitely leave more space between you and the vehicle(s) in front...:-)
PS
It takes quite a bit of practice to perfect cadence braking, so finding a quiet stretch of road and getting in some practice will pay dividends if you do need to bring it into use.
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What's for you won't pass you by
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PS It takes quite a bit of practice to perfect cadence braking, so finding a quiet stretch of road and getting in some practice will pay dividends if you do need to bring it into use.
Does anyone prcatice ? or is it the won't happen to me so why waste time.
On anouther point I saw the Think! (Gov) ad last night on the BBC which surgests Counting elephants for the 2 second gap or a ditti or anything that lasts for 2 seconds. this is all very well but at 1am most are in bed so why do the ads for the gov departments run so late it can't just be money !! why not make every other ad for a program on the bbc a govenment ad.
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"why not make every other ad for a program on the bbc a govenment ad."
Because Britain is not Soviet Russia ? :-)
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Another sure reason to buy RWD. Steering is far more effective under heavy braking - older Beemers could be very "interesting" under un-ASB, un computerised braking.
why not make every other ad for a program on the bbc a govenment ad."
Because they are the nearest we have to an oppostion in this country at the moment.
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Does anyone prcatice ? or is it the won't happen to me so why waste time.
Yes, and I suggest that whenever anyones on a long straight road with nothing behind you you stamp on the brakes to see what happens. See what the difference is with the brake hot and cold (worryingly high in some cars), see how straight the car stops, see just how much force it takes to lock the wheels in the dry and in the wet.
Its a lot better to find out when there's no other cars on the road than when your and other lives are in danger.
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I read often, only post occasionally
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If road surface was dry then option (a) as you will stop quicker than attempting to cadence brake. Cadence braking (or ABS in automated guise) doesn't give better stopping distance, it simply allows you to steer under heavy braking. If road is wet I would try the cadence method as I don't want to risk a skid on a slppery surface and lose control.
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Maximum Braking occurs the instant before the wheels lock-up.Both cadence and ABS can only lengthen the distance over this optimum but few if any drivers could ever achieve this optimum.
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Also you missed out an option C.Try to run onto the hard shoulder or onto the ground off the road-anything to avoid the tail-end collision.
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Actually, that's one of the reasons I try to use the left hand lane as much as possible. However, if I was in a situation where I ever needed to run onto the hard shoulder, I would have to admit that I have serious problems with my driving.
The problem is that maintaining a safe gap on today's motorways is near impossible. Every time you make a 2 second gap, someone takes it, and you have to make another, and another...
Disagree with comment about Beemers being easier to control under heavy braking. Having stamped on the brakes while one was tailgating me, I was shocked to see him fishtailing all over the road when I looked in the mirror. It was a learning experience for both of us!
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Not that old. I would have put it within the last 10 years, easily.
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That's a long time - especially in BMW world.
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Exactly Adam. I have provoked a "fish tail" out of the E46 I had
I think that this was down to a greasy (diesel I think) road and tyres that were well past their best, Never had a problem of late. Regardless of how good FWD cars have become - and I concede that some are very good, you can't overcome the sheer physics of a driven set of wheels having to deal with steering effort on both deceleration and to a greater extent acceleration.
How well maintained would a ten year old car be as well ?
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I can agree with the suggestion that RWD cars like BMW are likely to be more stable under braking.
I think that the fundamental reason that RWD have better braking is that they are more likely to begin with a better weight distribution, so their rear wheels actually contribute something meaningful to the total braking force, instead of being strangled by, sometimes very restricitve, pressure reducing valves in the case of most FWD vehicles.
If a RWD vehicle begins with a good weight distribution, and the ratio of the height of the centre of gravity divided by the wheelbase is low (i.e. the car is low and long), then there will be less foreward weight transfer under braking, and the rear brakes can continue to contribute even under high decelerations.
Compare this with short FWD vehicles (I'm thinking original Mini as an example), and the rear brakes are close to being an annoying irrelevance, really only there for legal reasons, and to provide a handbrake (unless they lock up, when they can cause havoc!)
Number_Cruncher
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Not that old. I would have put it within the last 10 years, easily.
10 years is old. The average life of a car in the UK is only about 13 years.
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L\'escargot.
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to be pedantic, if the average life is 13 then 10 isnt old, since 50% of cars will last to be older than 13.
I suspect that 13 is not the average though. That would be an L plate, I dont see many cars that old on the road round here.
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