Safe Speed Forums

In another thread a discussion emerged regarding hard use of the brakes.

Some say we should drive in such a fashion that we barely need to use the brakes. Same say they are there to be used. Clearly similar issues apply to harder cornering and harder acceleration.

Safety demands that we don't exceed safe thresholds, but clearly actually planning to use the brakes moderately hard doesn't automatically indicate that our action will be unsafe. Any reduction in safety from 'spirited' or 'enthusiastic' driving may need to be balanced against the practiced skills that will be available in an emergency.

Then there's an economic argument. Is sufficient time saved to justify the increased costs associated with brake and tyre wear? How do we find the right balance? Does driving pleasure influence the balance? (It does for me.)

Clearly some cars are designed for 'higher performance' than others. Certainly this means they are capable of greater acceleration. How much of that performance should we use on the road? How much performance do we want to pay for?

Personally I see no harm in using the performance that you have paid for, but I also believe that our braking and cornering plans must always leave a margin for error.

On the other hand, I can see great benefit in attempting to drive without usig the brakes at all. Doing this from time to time as an excercise helps you to plan far ahead. And planning far ahead is hugely important to safe driving.

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Paul Smith
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I was wondering whether to reply in the other thread and risk diverting its flow further - glad you've started this one, Paul.

I personally am a great believer in gears for going and brakes for stopping. Ok - I have an auto, but felt the same way before I got those.

Engine braking is to me supplementary for long descents where risk of brake overheating would otherwise leave me with nothing for the unforeseen events.

I used to change down all right - but to be in a position to be able to exploit the engine, not to get the revs up to slow the car down.

Three advantages:

1) Far less wear on engine mountings and all the transmission components (particularly the diff and drive shafts). This lot is much dearer than a few sets of brake pads.

2) One keeps the feel of the brake pedal for more abrupt requirements.

3) Less vrooom - better for passengers, bystanders and residents.

With regard to high performance cars, i feel it is safer drive such a car well within its limits rather than a low powered car near its limits.

I drive a moderately powerful car, 2.5l mondeo, its top speed is 130ish.

When people ask why i drive such a car they assume that i use this available speed ( which perhaps says more about their driving than mine ), yet often it turns out they have points on their licence whilst i do not.

These points are often in 30/40 limits where any car on the road can be driving too fast.

My car gives relaxed cruising, with power in reserve. Overtaking can be carried out decisively, and the brakes and tyres are designed to cope with a higher speed than a smaller engined model - but i have never taken it over 90mph. There is the drawback that wide, low profile tyres are useless in snow.

By using positive acceleration where safe, i have found that even though i aim to keep to 20/30/40/50 limits i very rarely get tailgated. Once a car has caught me up, but then seen that i am not dawdling, they usually drop back.

I try to use acceleration sense ( not the gearbox ) for minor adjustments in speed, but if brakes are needed then i will use them, and aim to use them once and fairly firmly - so the car behind knows that i am really slowing down and not just comfort braking like so many drivers do these days, the constant flashing on and off of brake lights at the slightest bend.

I used to try and brake as gently as possible all the time, but an afternoon of instruction with an ex-Hendon instructor showed me how being positive ( not harsh ) with the brakes increased safety behind and in front. It is clearer to cars behind that you are really are slowing down, and makes the approach to the hazard less rushed.

I drive a motorbike (a Suzuki SV650) and a relatively powerful VW.

When driving my motorbike, I will often give it the wellies from lights or wherever but will very rarely exceed the speed limit unless it is safe to do so and even then, unlike a large number of fellow motorcyclists I will keep it under about 90 even on the straightest of NSL roads (Notwithstanding the fact that the windblast on my motorcycle helps keep the fun factor there at legal speeds)

I always treat my bike with utmost respect and use all safety measures available to me when slowing down/braking/planning maneuvers - for example when approaching a roundabout - I'll normally perform an over the shoulder check, left and right mirror checks, then start to gear change down while blipping the throttle to get me into a responsive gear while using the engine braking characteristics of a V-Twin to slow me down to a speed I think will be suitable for the roundabout. I'm normally at this speed about 50 yards before the croundabout which gives me time to use the brakes should they be required. This way I'm alert, I have good spatial awareness, and I'm riding my bike at a good stimulative level - plus it keeps me fast and smooth.

I tend to lean towards "over trusting" the safety equipment in the car - ABS coupled with good tyres and alert driving is likely to get me out of a situation should one arise (particularly on a bend). On a bike, if you put the brakes on when you're going round a corner, you're either lowsiding, highsiding, or going straight into the hedge opposite. You have to get it right before hand.

There's no doubt riding a bike has made me a safer driver all round while still being able to use a lot of the performance characteristics available with both my bike and car.

Still no points, no crashes and it's not down to luck. The sad thing is I know if I continue driving/riding like this, I will get a 35mph in a 30 hit from a GATSO sooner or later

Martin

In todays traffic with many beefy disk-braked all round cars I feel that the braking capability of my car is quite badly mismatched with its performance. However, I've never found this to be an issue for 2 main reasons. 1. The car in front vary rarely performs anything close to an emergency stop and 2. I aim to leave a bigger then normal gap to compensate, plus the usual but important advice of looking as far ahead as possible. It's always best to be proactive then reactive to bunching in traffic by dropping back a little. The only time I ever find this to be a problem, albeit it a minor one is on a motorway. My slightly but not excessivly increased braking gap is seen as an invertation to pull into by some drivers. Not a problem if they are only using it for a moment to reach the exit, but an issue if it's in the 3rd lane.

As for how much braking effort you should use and how much you should keep in reserve is one that in IMO differs depending on the road and how busy it is. If its a quite country road and by using a decisive amount of braking capacity would enable me to make good progress then thats what I would do. If however, it is a busy trunk road then I usually plan ahead so that I don't require as much if any braking force. This of course will depend on whether I have to accelerate to catch the traffic in front - too much and I will aim to keep tighter on them through the bends. Similar principles apply in town - looking far enough ahead and predicting traffic movements and traffic lights can negate a lot of brake usage. How many times do you see people hurting forward to a set of red traffic lights only for you to follow at a moderate speed and keep a little momentum on for when the lights turn green? I'm always mindful of course not to cause frustration for traffic behind me - a balance should aim to be achieved.

I'm pretty much with SCE on this. The firm and decisive use of brakes is clearly a useful weapon in the defensive driving armoury. You can illustrate this by visualising yourself as driving the car behind yours.

If the car in front lifts off 400 yards from the next hazard and coasts up to it then the first warning you get is when you find yourself creeping up on them for no apparent reason, with the hazard still a fair distance away. If instead they begin a progressive braking application at a "reasonable" distance from the corner you are (a) more likely to anticipate it, and (b) will get a clear indication from their brake lights. Both make maintaining a safe following distance a much more natural process.

To take an extreme case, how about when someone is aggressively tailgating you? If you gently lift off he will always close up a bit more before he takes any avoiding action, whereas the shine of the brake lights as you start a progressive brake application will at least give him the opportunity to maintain or increase his following distance as you pull up.

A further point is that brakes need to be used to be kept clean of corrosion. If you don't brake reasonably firmly on a fairly regular basis then disk calipers & pistons are at risk of seizing, and the discs of building up a layer of scaly rust, which actually reduces their working life. In fact, I wouldn't be surprised to hear that the correspondent who gets 100k out of a set of pads hasn't had half of them in contact with the disc!

And a personal thing: I actually quite enjoy the sensation of firm, decisive braking. I'm not talking about standing the car on it's nose here, but I have a car with pretty big brakes and using them firmly - though still well within their massive reserves - is to me as much a part of the driving experience as enjoying brisk acceleration and plotting a smooth line through a series of bends etc.

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I'm in favour of this. I think that anyone who is driving so fast that they need to consider the dry, technical issues of breaking performance is missing the trick entirely – people like this probably think of their car as an amusing hobby (as promoted by Top Gear and similar shows) rather than the potential death-trap it actually is. I have no problem with people doing this at their own risk, on a private track. But please don't involve me, on the public roads

If you attempt to drive without using the brakes at all, you build up a truer picture of the reliance you place on luck and technology – two things that can desert you at any point without warning.

If you drive so fast that you need to consider breaking performance, you will never know your true skill level because you are relying to technical tools to substitute for skill. You will have less margin when your luck gives out, and no margin at all when your technology lets you down.

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I use engine braking over the foot brake quite a lot, but I think it can be over done. As has already been said, if there's someone behind you it's handy if they know that you're slowing down. If the driver behind is sharp they'll often anticipate it, but you can't rely on that. Depending on what's behind me I'll often rest my right foot on the brake just enough for the brake lights to come on (IMO it's worth spending some time on the driveway finding out how hard to press the pedal to turn on the lights if you use engine braking a lot).

I'd go along with the idea that it promotes thinking ahead, and maybe makes you think more about throttle use. If you intend to slow for a corner without using the brakes you won't be accelerating up to it racing driver style. I find that I've adopted a much smoother style of driving since I began using the brakes less - more like a sine wave and less like the Alps. Also, and this may be just me, I find that a smooth journey is less aggro and stress, even if I've had to deal with the same traffic jams, roadworks and idiots as I would have had when driving more <ahem> keenly.

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Do you apply the same logic to all the other technology in your car?

Presumably when it rains you never turn the wipers on, as this would be relying on technical tools to substitute for skill and you will have no margin when the technology lets you down.

I guess at night you leave your lights off and use your skill instead, rather than trust that they won't break down. etc etc...

I think you need to take a step back, and realise that when you step in a car you are trusting your life to technology, whether you like it or not. If you aren't happy with the level of that risk then all you can do is stay at home, or perhaps buy a newer car from a manufacturer with a good reliability / safety record, and pay the best people you can find to maintain it.

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You can see the obvious, clear and undeniable distinctions between the scenarios you present, I sure, but I'll address it anyway.

You activate your brakes by an event that is often and likely to be synchronous with danger and hazard. Failure of your brakes results in instantaneous danger. And putting on your wipers and lights won’t do much good!!!

The key points for wipers are - whatever your driving style, turning on your wipers when it rains is an advantage. Your wipers are activated (and this is key) by an event (start of rain) that is not (or is unlikely to be) synchronous with a danger point. Failure of your wipers results (or is likely to result) in a non-instantaneous visual degradation that can be accompanied by braking.

Similarly, the key points for lights are - whatever your driving style, turning on your lights when it grows dark is an advantage (unlike excessive use of brakes). Your lights are activated by an event (start of night ) that is not (or is unlikely to be) synchronous with a danger point. Failure of your lights results (or is likely to result) in a non-instantaneous visual degradation that can be accompanied by braking.

I’m sure you can see the motif here. Speed, and it’s counterpart, braking, are (as usual) special cases.

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No, I see very little distinction. Have you ever actually suffered a total failure of lighting or wipers, at a moment when they were needed? Suffice it to say that when they are just like brakes - when you need them your reliance upon them is virtually absolute.

Like Paul said earlier, practising driving without your brakes is a very useful learning exercise, and teaches a great deal about forward planning.

I used to teach dinghy sailing and did all sorts of tricks to get pupils to learn to use their peripheral skills, eg sailing blindfold or with the rudder removed. But I wouldn't expect them to go away and sail everywhere like this.

Braking is an essential part of driving, and as important a skill as (say) steering. We shouldn't avoid practising the technique frequently.

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I have tried both, and tend to do a mixture of the two depending on mood and conditions - I have often gone hundreds of motorway miles without touching the brake pedal at all - anybody who uses their brakes all the time is undoubtably tailgating, and knows it. At other times, I want to know what the current conditions are going to be like, so for example when it snowed last, I found a dead quiet bit of untreated road, and delibrately tried an emergency stop

I am interested in whether those advocating not using the brakes have considered the unforseen consequence, in that when your brake system is dirty, or dusty, or wet, or cold, that the actual braking performance is significantly worse than when the brakes are clean, dry and warm. It is something that I have noticed in many cars, but especially when coming off the motorway after a reasonable distance of not using brakes, the braking ability is seriously degraded until several goes at hard braking have either cleaned or warmed them up. Then normal braking is restored. Typically now I will brake with my left foot while maintaining power with the right, in order to achieve this without confusing other drivers by braking hard for no reason - it looks like gentle braking on the slip road, but in fact is hard braking countered by an unchanged throttle position.

Comes under the heading of driving to the conditions, I feel. The condition of the road is what we usually think of when we say that, but perhaps we ought to consider the condition of the car as part of it too.

As for not using the brakes, I don't think that's realistic in day to day driving, and not just for the reasons you've given. Personally my brakes get enough use when stopping for traffic lights - plenty of them near me and I can't think of one offhand where engine braking would be appropriate. Not using the brakes in a given situation if engine braking will do the job for you, that's a bit different. There's plenty of places where easing off and maybe dropping a cog will do the job providing I'm not approaching too fast. On a normal journey there will be times when I slow on the brakes and times when I slow on the engine. Urban and suburban journeys will be almost entirely on the brakes, whereas on faster rural roads I can use the engine and/or gears. Almost invariably when engine braking I am covering the brake pedal, or if someone is behind me I touch it just enough to switch the lights on. I think making good use of this can be a handy part of a driver's skill set, but part of that is clearly knowing when it's appropriate and knowing when it's not.

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Make everything as simple as possible, but not simpler - Einstein

Yes, but wipers or lights fail asynchronously to hazards. Which is the opposite of brakes, which fail synchronously, i.e. always when you need to use them most.



Perhaps a bit of practise is good, but routinely operating on towards the upper limit of technical performance is not, although you would not gather that from most TV shows about cars, which seem to encourage people to live dangerously.



I like sailing too. I can recommend 5 lakes land and the Okanagan Valley.

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Actually, it is your approach which introduces that very paradox! If you only ever use your brakes for emergencies, then by very definition you will only ever discover a braking failure in an emergency.

However, if you use your brakes routinely and decisively, as a routine part of most driving maneouvres, then if they should fail the odds are greatly increased that they will fail when you are making a minor speed adjustment, rather than in a full-on emergency.

And your point about wipers or lights failing asynchronously to hazards is nonsense. The hazard wipers deal with is water, the hazard lights deal with is darkness. That's when you use them, and also the time when you will typically discover any failure in the system.

Your approach to braking seems akin to managing without wipers during light to medium rain, and only actually turning them on if it is torrential. Thus you actually increase the odds of any failure only being detected at the time of greatest need.

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Nice try, and I can see that I should have made things clearer. I’m not literally talking about mechanical brake failure, but the total technology round-trip, i.e. the ability of the technology to save you from crashing. It may work almost all the time, but if you rely on it in dire situations, the 0.0001% of the time when it can’t extricate you from the mess you have made may kill you.



Yes, indeed. But it doesn't go dark without warning (total eclipse of the sun, perhaps?), and it doesn't rain torrentially without warning (when is the monsoon season in Cambridgeshire?). Other than that, darkness and rain come on progressively. Failure may happen during use, but there is nothing anyone could do about that, anyway.

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I had an interesting experience over the weekend. I went to a race track drive day with the WRX club as an instructor for my daughters boyfriend. He had never been on a racetrack and was very keen to learn.

Turn 1 on this track is a particularly nasty off camber right angle left bend which is approached at speeds up to 200kph. I picked a brake point at which I felt anyone could easily slow from and told him to brake at that point. We did not seem to be slowing very well so I told him to BRAKE! He said he was braking as hard as he could and we weren't stopping.

Well, we came as close to the kitty litter as I felt comfortable with so I told him to brake earlier next time. He did but we still barely slowed enough for the corner.

Next time out I said I would drive the first lap to show him lines etc and as we arrived at the first corner I figured I should be conservative and braked at the earlier brake point using very aggressive pressure.

Well, after pulling him off the windscreen (not literally) I concluded that what he felt was FULL braking was barely pressing the pedal. This has completely opened my eyes to the problems faced by inexperienced drivers.

He simply had no idea how hard he could brake. I could have completely stopped the car BEFORE the corner using the later brake point and yet we almost ran off the track because he did not comprehend how hard he could press the pedal.

Back to the topic though, I use brakes and engine depending on the situation. When I am trying to be totally smooth I use the gears and slow early and gently. When I am feeling a bit more "spirited" I will slow much later and brake firmly. It all depends on the mood.

One thing I ALWAYS do is to reduce the pressure on the pedal just prior to stopping to ensure a smooth stop. This applies even more when performing an aggressive stop.

I always try and imagine a bowl of water on a passengers lap and attempt to stop smoothly enough not to spill any water, even during an emergency stop!

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Ross

Yes I'm a hoon, but only on the track!!!!

But Ross, the surface of the water will take up an angle around 45 degrees to the horizontal with an emergency stop!

But I know what you mean - 'smooth' means controlling the rate of change of g force, not the absolute value. One might say: 'gentle' if one was describing control of the absolute value of g.

To brake smoothly, one gradually builds up the pedal pressure to a maximum. At the end of braking one gradually reduces the pedal pressure to zero. It doesn't matter what the maximum value is (from the point of view of smoothness), it matters what the rate of change is.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Quite true, SS, but in the WRX that M3RBMW is talking about things can get a little extreme... anacdotal evidence from scoobynet, says that coffee dregs left in the cup-holder of an Impreza Turbo have been sprayed onto the passenger door without any going on the floor!

If true, then the lateral force while cornering is in excess of 1G, so I expect that similar can be achieved under braking. Certainly on a test drive my wife brused her ribs against the seat belt when we tested the brakes, and she knew I was going to do the emergency brake test in advance.

A good opportunity exists to check the smoothness of your driving on the Trans-Canada highway in British Columbia. In the passes in winter, you drive at around 120 kph on top of thick snow. Braking is not a real option, because of the cliff which drops down a few hundred feet down through the woods to the railway in the chasm! After a few hours of that kind of driving, you leave permanent imprints of your grip in the steering wheel, and you are ginger with the brakes for the rest of your life!

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