Conference terri::cars_uk

    There's a black box under the bonnet, and an orange warning light
    saying "ABS" that comes on for a few seconds when you turn the ignition
    on.
    
    
    John

    On the subject of ABS, I've just ordered a car with this option and
    wondered as the car has discs on the front and drums on the rear, does
    the ABS only act on the discs, hence you could still get rear wheel
    lock-up or does it/can it act on the drums as well, OR do they fit
    discs all round if you go for an ABS option ??
    
    Advice please - Doug

    
    Presumably it acts on the hydraulic system and so affects all the
    brakes regardless of whether they are drum or disc.
    
    Mark

I would have thought the same as Mark, but the Ford Escort system circa '87 only
had sensors on the front wheels. These were driven by toothed belts off the 
front driveshafts.

When a sensor detected imminent lock up of either of the front wheels, it would
momentarily release the hydraulic pressure in the brake circuit to the wheel.
However, since the pressure circuits were linked diagonally front to rear, this
also had the effect of releasing the brake pressure on the rear wheel on the
opposite side.

It was almost ABS - but not quite ie. a typical low cost Ford solution. Most
car manufacturers these days use an ABS system with sensors on each wheel. I
don't know whether the Ford front wheel system is still in current production -
perhaps somone out there knows what Ford fits on their front wheel drive cars
now.

Oh, and by the way, the drive belts on the Ford system go slack after about
12000 miles. If you don't get them tightened up at a service, you may find
that that the ABS ain't around when you need it.

Dick

    My Renault 21 was ordered with ABS. The tell tale amber light on the
    dash gives it's installation away as does the shiny brake disk visible
    at the rear in place of the non-ABS equipped cars that still have
    drums. Depending on the type of system, you may also hear an electric
    pump running for a few seconds when you switch on the ignition.
    
    That's probably why the option cost �1100........... but was worth it
    as the disc-all-round braking is infinitely better than disc/drum
    combination.

    a. The new Ford escort/orion has an electronic ABS, the mechanical is
    dead.
    
    b. usually when you look closely at the spec of cars it says something
    like "Drums Rear (disks if ABS)" They usually use disks, as 1. it's
    easier to fit the detection system, and 2. it gives superior stopping.
    
    c. You can usually see ABS from under the bonnet. If you follow the
    brake pipes from the brake master they go to a big block/box with a lot
    of pipes on and electrical connections. This is the ABS actuator. If
    the pipes dissapear off under the car, you've not got ABS!.
    
    Richard

    
    Thanks...
    
    

Something I've been wondering for the last few months.  Disk brakes cost about
the same per wheel as drum brakes.  Disks give better braking and are easier
(IMVHO) to maintain.  So why does anyone fit drums to cars?

RE base note, the Sierra (for example) has drums at the back on non-ABS cars,
and disks all round with ABS.

Scott

Just a little side note here.  Some statements have been made that 4 wheel
disc brakes provide better stopping than disc/drums.  Generally I would
have to say this true, however, Ford has proven you wrong.

Back in the late 70's when Lincoln had the Mark VI or VII out (they all
blend together now) one of the options you could buy was 4 wheel disc brakes.
Mind you, this beast weighed in at around 4000 lbs empty!  Anyway, the
published stopping distances for the disc/drum setup from 60-0 mph was 6 to
8 feet shorter than the optional (and more expensive) disc/disc setup!

Dave

    
    Re .4
    
    The "cheapo" Ford ABS was in fact a Girling system and sold on
    other FWD drive cars as well. As another note said, this system
    only used to operate on the front wheels.
    
    R.

re.0:

ABS is now standard on the SRi.

Dave.

	Isn't that typical, my wife's SRi is a year old and doesn't have
	ABS.  Oh, well, I'll have to wait until the next one.  Mind you, I 
	can't remember being in a situation where I felt the need for ABS...

	As for drums versus disks, Derek is right, drums are a lot simpler and
	easier to make.  Also, drums are less likely to get wet and slip; so
	disks at the front and drums at the back offers a pretty good 
	compromise.

	Dave

    ABS is automated cadence braking. It is useful where an emergency
    forces you to brake hard and steer at the same time, but it is also
    useful for straight line braking in emergency conditions where the
    skill of the driver is not up to cadence braking a dozen or more times
    per second.
    
    In four and a half years of ABS driving, I have used it (I think)
    twice. Each was caused by another driver crossing my car's path when
    they shouldn't oughter, and each saved certainly bent metal, and
    possibly bent bodies. For me, its value is beyond price.
    
    Steve

So why do 9" cortina disks cost c. �13 and 9" escort drums cost c. �35 ?

Puzzled (and broke ;-)

Scott

    
    Surely the drum includes the whole mechanism for braking.
    
    You'd have a lot of trouble stopping a disk braked car with no
    callipers!
    
    Mark

Yes, I know a caliper costs a lot more than the slave cylinder for drum brakes,
but then the drum brake's backplate is a heavier-duty job (ie costs a lot more)
than the (optional) one on disk brakes, and so on.  For the brakes on the Moss
(9" cortina disks and 9" escort / capri drums) the overall cost "per wheel" for
new parts is about the same.  I'm just angry 'cos I got ripped off by the guy
who supplied the rear axle / brakes...

Scott

Ahh! I've just realised what you meant.

No, the �35 is not the whole braking mechanism, just the drum (bowl-shaped
piece of cast iron).  On top of that you need slave cylinder, brake shoes,
backplate, hold-down springs and clips, etc.

The other problem with drum brakes is that you have to take the centre-lock
adaptor spline off to remove the drum and get at the brake shoes...

But then that's my fault for wanting to put wire wheels on Ford hubs ;-)

Scott

    Thanks to .5 re the Renault 21 cos I've also ordered a Renault and as
    it is an electronic system, I guess I benefit both by ABS and Discs all
    round and the option cost is just under �1000.
    
    Doug

    
    I think I'd disagree with you Derek.
    
    The disks all round setup on the Renault gives me a lot of confidence
    on the road, and certainly gives much better retardation than a
    disk/drum setup would.
    
    Disks all round are essential on any car with good acceleration and 
    top speed. If you are travelling at 70 mph on short straights you 
    need good brakes to slow for each bend and that's just as true on 
    country A & B roads as on the racetrack.
    
    Mark

    
    You could be right. The 5 GT Turbo has vented front disks whereas
    lesser models have ordinary disks. The braking effect is MUCH for
    noticeable on the GT Turbo than on the lesser models, but this 
    could be a combination of the greater tyre area and the ventilated
    disks being able to disperse the heat quicker and therefore brake
    more effectively. The ventilated disks MAY be bigger too!
    
    Mark

    Rwe -1...
    I agree with Mark (?) Discs all round on the Renault 21 have absolutely
    Transformed the braking when compared with the disc/drum set-up.
    
    We don't all want to get to the next bend at the speed of light and
    then go round it on two wheels and the doorhandles..... ;^)
    
    How about the load luggers who tow a large caravan? (or perhaps a large
    trailer stuffed full of racing car, spare tyres, tools and replacement
    fuel pumps? 
    
    It was worth the grand or so that the better braking cost 1) to impove
    the braking under normal conditions but also 2) to know that I can now 
    stop my van from overtaking me when I brake........
    
    Lets be careful out there.......

disks at the rear wouldn't fade as much as having drums at the back end
drum brakes tend to warm up & stay that way since its harder to cool them

besides a set of disks gleaminh through alloy spokes look nice!


...art

    Is it true that disks give a greater swept area for a given diameter?
    
    In that case disks all round is ALWAYS going to give greater
    retardation for a given wheel diameter than a disk/drum combination.
    
    Mark

    My 21 has ABS..... the only times it has cut in have been when I have
    been a bit over-zealous with brake pedal pressure (greasy road and a
    leaf-littered road)...... the discs on the front are ventilated. I
    agree that most of the effort is put in by the front pads as they wear
    out about three times faster than the rear. However, by the time the
    car is loaded up to the gunwales with family, sundry junk a roof-rack
    full of bikes etc and then the van hooked on the rear, the rear brakes
    MUST be doing extra work.
    
    Mustn't they.....?

The swept area of the disk is determined by the size of the pads and the
diameter of the disc.  On the drum it's determined by the shoe size, diam
and the width.  You could have a very wide drum the same diam of a disc and
get more swept area.

Dave

    Isn't having an ABS car towing a braked trailer/caravan dangerous??
    
    I mean, if under panic breaking your ABS cuts in and stops the wheels
    from locking, what's to stop the van's wheels from locking and trying
    to overtake you???
    
    Or is it that the compression forces on the tow-bar will never be enough
    to lock the van's brakes?
    
    Huw.
    
    PS. I've never come across disk-braked trailers!  
    

If the ABS releases the brakes on your car, that will reduce the compression
in the tow bar link (as the trailer is still braking), and hence reduce the
braking force of the trailer.

So you get ABS on your trailer for no extra cost...!

Scott

    Re .32
    
�If the ABS releases the brakes on your car, that will reduce the compression
    
    That only applies when ABS sensors detect car wheels locking - not the van.
    
�So you get ABS on your trailer for no extra cost...!
    
    Chances that van wheels would lock sooner ?
    
    
    Whatever the theory, I would've thought 'panic' braking with a van
    or trailer to be pretty dodgy anyway, ABS or no ABS.
    
    J.R.

    Closing my own loop (somewhere back in this note) I just took delivery
    of the new car with ABS.  Exit drums on rear, entrance Discs all round.
    
    Very nice.
    D

    
    Has anyone had trouble with ABS in the current conditions?
    
    I've not had a car with ABS before (or even driven one as far as I
    know), but the Calibra has it and far from being a bonus on snow and
    ice it seems to be a real pain. If the wheels start to lock on ice the
    ABS starts to work, but then just seems to lock the whole thing up (the
    pedal feels as if the servo has packed up). The only way to get round
    this problem is to pump the brakes in the good old fashioned manual
    ABS method! :^)
    
    I presume the problem is that the wheels are locking all the time that 
    the brakes are applied.
    
    Mark

    I've had no problems with my ABS.  If you jam the brakes on (pretty
    stupid thing to do) the pedal jumps up and down as the pressure is
    released and re-applied, but it doesn't slide at all.  After hearing
    that ABS was a pain in snow/ice I don't see that its much of a problem
    - maybe I could stop a little better by snow ploughing stationary tyres
    but I'd rather have the ABS.
    
    What sort of system has the Calibra got?
    
    Rob

    
    What do you mean, what system?
    
    Mark

    I'll be getting ABS on my next car. The people I have talked to have
    said that ABS is definately a bonus this weather. Sounds to me like
    there is a problem, Mark.
    
    - Roy

    
    Ummmm,
    
    I'll have to look into it. The ABS light works ok and it seems fine on
    a mixed surface (ice and tarmac), but I seem to remember a comment that
    ABS actually extends the braking distance on snow/ice. Is it Audi who
    allow you to turn it off on icy roads?
    
    Mark

    There is no doubt that the stopping distance may be longer with ABS,
    the real advantage is that you can control the steering during a
    "skid".
    
    - Roy

    
    I think I'll have to find a quiet stretch of snow covered road and 
    work out just what the car is doing.
    
    Mark
    

    sounds as though the ABS thingy is doing its thing just fine. My
    Renault has ABS and when any of the wheels lock the brake pedal goes
    solid, too. There's a fast clicking sound/feeling through the pedal and
    as a previous noter said the electric pump/control unit is relasing and
    reapplying the brake pressure to prevent the wheel relocking as the
    pressure is reapplied. The pump can do it faster than you can manually
    so you are actually negating the advantage of having ABS by releasing
    the pressure on the brake pedal and re-applying it. If you paid extra
    for ABS...... you could have saved yourself some money.
    
    It's unnerving, but believe me it works. Stopping distances are
    marginally longer but you lose that awful feeling of incapacity to
    decide where to go as you DO keep all your steering capability.
    
    I found a nice slippery road surface just after taking delivery and
    practised a bit which was good training for changing the automatic
    reaction of releasing the brake pedal. It takes a bit of practise but
    the trick is to keep the pedal down.

    
    That could be it. I must admit as soon as the pedal goes solid I've
    been lifting off. As you say, some practice is called for.
    
    Mark

    Mark - I think you may have hit on why the ABS felt so bad - you need
    to keep the pressure on and not try to do the ABSs job for it.
    
    It's it bit sad that ABS "encourages" a braking technique that is
    dangerous for non-ABS.  You need to take account of that and adjust for
    different cars.
    
    Rob 

    
    Or in my case adjust to allow for ABS! :^)
    
    Mark

    I think the key thing is to practise with the new features of the new
    car - as you would anyway.
    
    Lots of developments over the years have required different techniques
    - moving to four wheel brakes comes to mind, and moving from cable to
    hydraulic brakes.
    
    My view of ABS is that it is the stage of development after hydraulic
    four wheel brakes, which all cars for non specialist use should have.
    Whereas before I would drive gingerly and, as far as possible,
    brakeless in snow and ice, now I will, if the road is clear for a good
    distance in all directions, build up speed and stand on the anchors
    just for the sport. The car just stops, and you can slalom under full
    control at the same time. Great fun, and you learn about controlling
    the machine in marginal conditions to boot.
    
    For the sake of the safety of my family, I will not order another car
    without ABS; in exactly the same way that I would not consider a car
    without doors.
    
    Steve

    Mark,
    
    	i friend of mine in the office has a Calibra, and last Friday he
    complained that the ABS wasn't working for most of the journey, it only
    became effective as he arrived at the office.
    
    Perhaps it had frozen up?
    
    mb 

    Can't speak specifically for Calibras, but most ABS systems are kind of
    switches in the hydraulic system. If the brakes work, I can't see that
    there is anything in the ABS bit to freeze.
    
    Steve

    
    I've got ABS, & have no especial problems with it in low friction
    situations -- but note that Audi did provide switchable ABS on the
    early Quattos (the grunty variety, not the slow ones). They made the
    specific point that braking on snow & black ice was worse with ABS --
    I suspect 'cos the brakes are always coming off due to locking, rather
    than ever working.
    
    Best brakes when there is no grip is engine braking, same as has always
    been the case. ABS doesn't alter basic physics.......
    
          

Re.-2
    
�    Best brakes when there is no grip is engine braking, same as has always
�    been the case. ABS doesn't alter basic physics.......
    
     No brakes work when there is no grip - try a parachute :-)
                                  ^^

    Re .51
    
    I have practised in a non ABS car on a slippery surface. I have taken
    some skid pan tuition. I accept it is possible to control a car on ice
    without ABS. It is also possible to control a car without any brakes at
    all, or missing a wheel. You then adjust your driving to the vehicle's
    capabilities and the limitations of road conditions.
    
    When driving a car with ABS, I am concerned if the ABS cuts in, because
    it indicates I have misjudged the adhesion. Playing in car parks with
    ABS enables you to find those limits, without finding a bollard.
    
    I would emphasise that my comments were specifically related to cars
    "for non specialist use"; I wholly accept that for rallying, racing or
    off road ABS may not be appropriate. However, I firmly believe that for
    Joe Public, who rightly or wrongly do not take their motoring to the
    levels that the members of this conference do, ABS will save life and
    limb. It has certainly saved the day for my family more than once - and
    I am not talking minor shunts.
    
    Steve

    
    
    Some of the new Quattro 80's 90's etc still have switchable ABS....
    I don't know if this applies to their 2WD counterparts

    

    
    OK, I own up. Comment on physics was short-hand.
    
    What I was describing was that it is often much easier to control a
    vehicle in any very low-grip situation purely on engine braking. True
    when taking a 4wd down some slippy 1 in 3, whizzing around on a skid pan, 
    riding a trials bike down some terrifying precipice, or merely playing 
    with the black ice on the way to the office.
    
    My own car has ABS, fwd, 150 bhp --  & wide low profiles that are all 
    but useless in very poor grip situations. Easiest way to keep the plot
    on the marbles is to stay between 3-6k rpm, & leave the brakes alone.
    
    Forgot myself yesterday, & got caught going into a slow bend in
    Sindlesham. Turned wheel at slow speed (>20mph) on 80 degree
    right-hander. Car went straight on, steering wheel very light --
    ditch straight ahead, no ability to brake as on black ice,
    & at approx 1200 rpm in 3rd. What a wally - if I'd been in 2nd,
    or even 1st, merely lifting off would have brought the plot back
    under control.
    
    All's well that end's well, but I cursed my stupidity. You can't be a
    lazy driver on black ice.
                 

    >> My own car has ABS, fwd, 150 bhp --  & wide low profiles that are all 
    
    Just like the Calibra.
    
    I found a quiet bit of road last night and stomped on the brakes. Sure
    enough the pedal went solid, but this time I kept my foot on the brake
    pedal and, hey presto, the car came to a graceful stop.
    
    I just hope I can remember to keep my foot down next time it happens.
    
    The trouble is I'd just managed to train my brain to get the foot off
    and back on the brake pedal when it locked up! :^)
    
    Mark

	My car has big fat tyres and is light and rear wheel drive, but the 
	only times that I've slid during this snow is when I wanted to.  You
	just have to drive as if there were ice, use the engine to brake and	
	avoid using the brakes except in a straight line (the way you should
	anyhow).  The car park has been very useful for practising in, 
	unfortunately, the snow's mostly gone and they keep gritting it.

	For me, I'm afraid ABS comes under the heading of gizmos that attempt 
	to compensate for bad driving practices.  Others include devices that 
	tell you its cold outside and that you're too near the car in front.
	What are eyes for?

	Dave

    
    Re .57
    
    And seatbelts and disk brakes... (semi :^))
    
    ABS has to be an advantage if it can allow you to keep control of a car
    once you are in an skid. Certainly it would pay to be aware of the
    situation and conditions and I've no sympathy for people who drive more
    dangerously or carelessly and then expect ABS to save them, but like
    many other new ideas which people have been resistant to (including
    high level brake lights :^)) it does and will reduce accidents and at
    the end of the day that has to be a good thing. 
    
    I've no sympathy with the arguement that it makes people over
    confident, only an imbecile would believe that the driver isn't the
    cause of 99% of accidents and those kind of people have accidents
    anyway!
    
    Mark

     �GERMAN INSURANCE COMPANIES Have proven cars with ABS have more accidents
    
    Could one of reasons be that at present ABS is mostly fitted to high
    performance cars, therefore higher risk.
    
    I can see the argument that ABS could give you a false sense of security.
    However I still think that it is an important step in improving safety.
    I've ordered a car with ABS _because_ it is a performance car, and
    whilst I don't intend to drive like a maniac, the thought of having ABS
    gives greater peace of mind. (This sounds as if I've fallen into the
    trap of having a false sense of security!)
    
    - Roy 

I tried mine out, on the first day of the snow, in a big empty space,
and it was quite interesting to go back and look at the tracks in the snow.
There was a definite "dottted line" where the wheels had locked and unlocked
rapidly, so it was definitely working.... but I still slid a loooong way !

Surely the point was made a few notes back.......ABS helps you to retain
control in conditions where you would otherwise be out of control.... 
but it doesn't do it for you !     ABS is a safety tool, just like better tyres
or better lights, but it doesn't make the driver any better.

I've got ABS, and wouldn't be without it, because it improves the odds for me
and my family - but I still have to drive within the limits imposed by the
car and the conditions.

In my last company, we used to make the hardware that tested ABS electronics,
so you won't catch me relying on it !!!! 

Ian

    
    Re .59
    
    Derek,
    
    As if I'd try and wind you up! :^)
    
    My argument (or the one I think I meant, you've confused me) was that
    no device (ABS or anything else) will stop reckless drivers having 
    accidents, but that a device which can help you control your car (or
    help Mr Average control his if you prefer) can only be a bonus.
    
    Isn't it true that Germans drive very close together at high speeds?
    ABS used to be advertised as stopping you in a shorter distance. If
    people believe this (no one here has cited it as a benefit of ABS),
    then they may be tempted to drive closer, but that is a driver problem
    not a problem with ABS. I didn't say that people do not become 
    over-confident if they have ABS, I said (perhaps slightly strongly)
    that they were foolish and wrong to do so. However, I doubt that 
    sensible drivers would drive closer to a car even if they believed 
    ABS would pull them up quicker (I know I wouldn't!).
    
    Mark

    
    One of the points made earlier was that ABS is 'one of the improvements
    which have occured over the years, such as tyres, etc'. I agree with
    this, but the big difference is in the way that ABS has been
    advertised. eg tyres - they are normally part of the car you buy, not
    something that you persuade people to pay extra for, - that only
    comes when they need the next set of tyres. ABS is an option which can
    be built into the car, but is (or was) something the manufacturers
    tried to sell as a factory extra - and so the advertising money spent
    was used to emphasise the "added safety to you and your family".
    Adverts told people they would be safer - and implied that braking
    would be improved - and many people took this to mean that they could
    drive with impunity in any conditions. Yes, Joe Public should not be
    so gullible as to believe things which are implied in ads, but if they
    weren't, advertising wouldn't work.  

    Some of the replies from people with ABS worry me a little!
    
    ABS stops you locking your wheels due to braking.
    
    It DOES NOT stop you from skidding, which can be caused by excessive
    acceleration, too hard cornering, too much engine braking as well as
    hitting the middle pedal!
    
    To say things like "i could slalom my car with ABS" are meaningless,
    because your lose control due to the tight steering manouvers, nothing
    whatsoever to do with the brakes!
    
    True that you are less likely to start skidding on a corner when you
    _brake_, but not true that if you corner above the limits of adhesion
    ABS will save you.
    
    At least *without* ABS you know exactly the road conditions and can start
    making alternate plans if you feel that braking alone is insufficent.
    *With* ABS all that you know is that you are stopping as fast as ABS can
    stop you, but how do you know exactly how fast that is?
    
    Hopefully you should never have to use this expensive "gimmick" if you
    are driving within your limits!
    
    Martin (the perfect driver ;-)) Bell

    Many valid points in the discussion.
    
    The problem with ABS systems (as with all devices) is that there are
    good, fair and poor systems (expensive, medium, cheap). It is well
    known that the good ABS test is to brake hard on a very bumpy, wet
    slope. Various systems brake very well, and at the other end of the
    scale certain systems don't brake at all.
    
    The real point of ABS is to NOT LOCK the front wheels. This function
    usually works well.
    
    Some ABS systems are weird HACKS. The VECTRA/CALIBRA 4WD system is
    probably the worst of these. The ABS really disconnects the shafts.

    >> At least *without* ABS you know exactly the road conditions and can start
    >> making alternate plans if you feel that braking alone is insufficent.
    
    How does ABS affect your ability to judge the road conditions?
    
    >> Hopefully you should never have to use this expensive "gimmick" if you
    >> are driving within your limits!
    
    Very true, but sometimes the limits can change so quickly that even the
    best drivers cannot adapt fast enough.
    
    I must admit, I didn't expect this kind of 'safety makes you
    complacent' attitude from CARS_UK noters. Would you all have said
    that wearing seatbelts was a bad move a few years ago? Or argued
    against introducing brakes which could actually slow a car down?
    
    Mark

    
    Re .66
    
    Doesn't the Vauxhall/Opel 4WD rear drive disconnect work IN ADDITION to
    the ABS?
    
    Mark

    
    Re. the last 10 or so...
    
    Having tried out the ABS in the Range Rover in anger over the
    last week, I can honestly say I've changed my opinion of ABS
    totally - it's brilliant!
    
    Unfortunately I did suffer from the overconfidence syndrome for
    a couple of days, until I slid gracefully off an uncleared road
    into an even less cleared field...
    
    Jonathan.
    

    
    >> Perceived Safety makes you complacent 
    
    True of any situation. For instance, anyone who thinks they're a 
    fairly good driver is increasing that risk.
    
    If the number of accidents have remained static since WW2 safety has
    obviously increased by an enormous factor or are there only the same
    number of cars on the road now as there were after WW2?
    
    Does any country EXCEPT Germany have figures to prove that ABS is a 
    disadvantage? Do you know what the figures actually said? Did more cars
    with ABS (of the same model) get involved in accidents or was it that 
    models with ABS (fast prestige cars in Germany) were involved in more
    accidents. This sounds like the same argument that says that Hot
    hatchbacks are inherently unsafe, simply because the way they are
    driven leads to more accidents. 
    
    Mark
    
    PS Am I going mad or would it not seem obvious that ABS wouldn't stop a 
    non-brake related skid?

    Re: .67
    
>    How does ABS affect your ability to judge the road conditions?
    
    Mark,
    
    If you brake with no ABS and your wheels lock, it is possible to ease
    off slightly until you are no longer skidding. Depending on how much
    pressure is required to brake without skidding you get a feel for how
    much grip you have on the road. We have all done it, hit the brakes
    hard on a wet road in summer and "whoops", it is a little more slippery
    than we expected, so we take things a little more carefully.
    
    Now with ABS, the only feedback is the fact that ABS is working (in
    fact from the sound of it, sometimes you don't even know that it has
    been activated). Unless your car is equipped with a decellerometer (or
    whatever it is called), you don't know how quickly you are slowing
    down because you don't know how hard the brakes are actually working.
    
    Thus you are not as aware of the road-stickiness!
    
    
    Sorry for being a little controversial.
    
    I would never drive without wearing a seat belt, but i do think that 
    things like ABS should be regarded in a similar way to things like the
    proton-10 (?) system that Audi fit to their steering wheels - a very nice
    safety feature, but i would hardly want to test it out!
    
    mb

    
    Re .72
    
    As far as I can see from my limited experience ABS doesn't stop you 
    doing this. The ABS starts to activate and you can either keep your
    foot hard down or back off the pedal. In the latter case, if the wheels
    stop locking the ABS will stop working.
     
    Re .Whatever
    
    Horse riding is more dangerous than motorcycling? Got any evidence to
    support this?
    
    Perhaps the reason motorcycle accidents reduce in the winter is that 
    motorcyclists all jump in their cars?
    
    One day you'll have to live with ABS 'coz all cars'll have it, just
    like seatbelts or disc brakes.
    
    Mark

>>  You are obviously 

>> a) above average intelligence
>> b) have been at least partly immunised against advertising hype

    Flattery won't help your argument! :^)
    
    From my cycling days I'd say that riding a motorcycle in snow and ice is 
    probably more of a real risk than a perceived one! Keeping a cycle
    upright on black ice is tricky, but on those near slicks that many
    sports motorcycles seem to have nowadays, I'd imagine it's near
    impossible!
    
    Mark

    
    I can't remember the figures quoted in the German mag, but I am well
    aware of the 'lies/damned lies/statistics' to prove your point articles,
    but I was satisfied at the time that the figures were 'fair', and had
    taken into account things like number of cars/types/with/without ABS.
    I think the % of ABS cars in Bavaria was much higher anyway - more people
    have new fancy Mercs, BMWs etc. 
>>    
    Perhaps the reason motorcycle accidents reduce in the winter is that 
    motorcyclists all jump in their cars?
>>
    Not necessarily (:-) ) - it's because more miles are travelled in the
    dark, and car drivers are more likely to see a headlight in the dark
    than in the light.  Those motorbikes on the road are also far more
    aware of the road conditions than the car drivers........

 > Mark, I didnt think you drove fast enough to use brakes?
    
    Whenever I've followed you I've always found simply lifting off was 
    sufficient to avoid tail ending you! 
    
    Mark

    According to the Big White Chief in charge of the Metropolitan Police
    Horses - "Nationally, more people are injured in horse riding accidents 
    than motorbikes, but more people are killed in motorcycle accidents"

    
    A minor injury I could put up with, being slightly dead sounds less
    acceptable.
    
    Mark

    
>>    A minor injury I could put up with, being slightly dead sounds less
>>    acceptable.
    
	At least your only dead once .... :-)

    
    re: last few..
    
        my motorcycle has been in my garage for the last 3 weeks having
    road salt/whatever they use carefully removed from all those places
    that it is likely damage (salt increases rust). In that time it has
    neither damaged itself or anyone else, however I have been bit by a
    horse that was in a stable. 
    
    Moral : a motorcycle is predictable, it willl only cause injury when
            being used in a way that it was not designed (stopping in a
            distance of 2 feet when a volvo pulls out in front of it is not 
            something it was designed to do, unless it's speed is under 5
            mph. Horses are unpredictable, they may cause injury at any
            time or place.
    
      I have heard that the Granada/ABS advertisement (where the granada
    misses the tractor) took more that 1 car to complete. The driver knew
    that the tractor was going to be in the road, but he still managed to
    damage more than 1 granada (what chance is there for ABS when you don't
    know the tractor/anything will emerge from a side turning ??).
    
     To enhance Derek's argument, when crash helmets became compulsory for
    motorcyclist motorcycle accidents increased, why?? because
    motorcyclists believed that they were safer, so they took greater
    risks (NB. motorcycle related head injuries decreased). Volvo drivers
    believe that there 'cages' will protect them so they rarely ensure that
    every manouvre is safe.
    
    
      Alan.
    
    
    * disclaimer.... I have nothing personal against Volvo's or the people
    that drive them, but I do see them doing some very risky manouvres.

    Horses are indeed statistically more dangerous than motorbikes,
    ask any insurance company. Horse riding is considered to be a
    high risk sport. I'd rather be on a horse than a bike in ice and
    snow though, they have better roadholding ;-)
    
    Mind you, a motorbike has never bitten me or stood on my foot...
    
    Do any bikes have ABS yet?
    
    Jonathan.

    BMW's are the only bikes with ABS at the moment.
    
    A long, long time ago, when I was a statistic, a student nurse was
    giving us (half a dozen bikers) a hard time for filling up the ward.
    The sister sent her off to the female ward and told her to count up how
    many girls were in there after having fallen off horses.
    She came back suitable chastened.
    
    Perhaps road safety might be improved by insisting that only boys ride
    horses and only girls ride motorbikes...
    
    Back to ABS - I find that the performance of my ABS brakes are improved
    several million percent in snow and ice by fitting winter tyres.
    Or to put it another way, driving on snow with 235/50 P-Zeros doesn't
    even allow the ABS to get a look in.
    
    Rob
    

    PS
    I just remembered, I did have a bike stand on my foot once - painful.
    I have also managed to burn myself on the exhaust before now...
    
    Rob
    

    
    Some recent replies make me wonder whether the writers pontificating on
    the evils of ABS actually have it, & have ever used it in anger.
    
    I have (both), & will not buy another car without it.
    
    I wish my motorcycles had it, but they haven't & I don't want a BMW.
    
    Before the pundits all rush in & say I caused my own downfall because
    of complacency due to ABS, the particular incident was that one well
    known to all motorcyclists -- the tunnel vision Volvo driver. As I was
    in the car with ABS, I swung round him whilst braking hard as he came out
    of side road -- regrettably, through no avoidable fault of my own, I would
    have been worse off on the motorcycle.
    
    Re one earlier -- you can't cause a skid by engine braking in the terms
    that I mean it. You can cause a skid by clumsy use of the drive line,
    but I'm talking about the use of engine braking in ultra-low grip
    situations. In those cases, you only change gear when at very low risk,
    (eg pointing in a straight line with good run-offs). When on black ice,
    rounding slippery bends etc, I would prefer to use a constant gear & use
    engine braking on the throttle in the 3k-6k band.
    
    The whole trick in these just-passable conditions is offering the minimum
    interruption to smooth power. Changing gear etc must break the ultimate 
    smoothness, regardless of your capabilities -- if only because, by
    definition, on a manual vehicle you interrupt the flow briefly whilst you
    declutch to match revs.
    
    Above is empirical, & may be argued against by others of different
    experience. It suits me & my vehicles, learnt the (sometimes) hard way
    based on 30 years on 2 & 4 wheels, on & off road, racing, trialling,
    rallying & touring. I still get it wrong, so alternative suggestions to
    stay alive always welcome ......
    
    BTW, no-one has mentioned that the 3-dimensional nature of motorcycles
    means you are vastly more aware of the nature of grip on every yard
    underneath your wheels than many car drivers ever achieve -- all to
    do with self-preservation (either of body, or wallet -- fibreglass
    repairs now getting very expensive!). I have a suspicion that today's
    cars are so much a sofa on wheels that we all risk becoming terribly 
    insulated from real feedback from the road until it's too late. 
    
    Not a judgement, more a sorrow. I suspect that fact lies behind much of 
    the comment on ABS & complacency. 	
    

>>
    BTW, no-one has mentioned that the 3-dimensional nature of motorcycles
    means you are vastly more aware of the nature of grip on every yard
    underneath your wheels than many car drivers ever achieve -- all to
    do with self-preservation (either of body, or wallet -- fibreglass
    repairs now getting very expensive!). I have a suspicion that today's
    cars are so much a sofa on wheels that we all risk becoming terribly 
    insulated from real feedback from the road until it's too late. 
>> 
    I agree completely, I think I mentioned it several back, after the
    comment about sensors to tell you the outside temp (which I am dead
    against - because no gadget is going to tell you about the icy patch on
    the shady corner, but that's a different rathole) The best sensors on
    the road are your own eyes/ears/skin - and the closer you are to what
    is going on (eg on a motorbike) the (hopefully) more in tune you will
    be to what is going on. 
    
    PS - I've had more burns from my cooker than the motorbike - is it more
    dangerous? :-) 

    
    re. 1276.85 And of course we all believe everything we hear on the
    radio - don't we ?
    
    No I don't know where he got his facts and figures from, but if the
    statistics are available he is the sort of person who would have
    access to them and I can't see any reason for him to 'invent' such
    a statment.
                                            
    An interesting rat-hole don't you think? 

    
    I must say I'm amused by this note - surely, the benefit of ABS
    is that it may save your life... 
    
    If you feel you rely on it, then you probably ought not be driving
    (my car has a good roll and safety cage, and sturdy seat belts - I
    do my utmost to avoid using them though!)
    
    Bill.

    Time to insert the wooden spoon and see what I can stir up!

RE: .90

Colin,

    I don't doubt the virtues of ABS, and will look for it on my next car
(I always buy second-hand so there aren't a lot around yet). However, I found
your note inconsistent:

>>    Some recent replies make me wonder whether the writers pontificating on
>>    the evils of ABS actually have it, & have ever used it in anger.
    
>>    I have (both), & will not buy another car without it.
    
>>    I wish my motorcycles had it, but they haven't & I don't want a BMW.
    

You won't buy another car without ABS, period. It clearly is something very
important and you are trying to emphasise this to the readership - at least it
made a big impression on me. Yet, you then go and spoil it by saying that it's
not so important that it can sway a purchase decision on a motor bike - it
ruined the affect of what you'd already said.

So should ABS be an all important decision forming criteria, or isn't
it? 

Cheers

Steve Simpson

    
    Sorry, Derek - all features were standard with the car... On the
    road, the limit on how fast you drive is prescribed by law and
    (more importantly) your ability to stop safely in the distance you
    can see. Obviously, ABS doesn't alter either of these criteria; but
    it may save your life when you make a mistake!
    
    As for comfortable levels of risk, I understand your view and
    even agree (for once). However, I hope an appreciation of the
    psychology of driving would mean I don't drive a car with ABS
    any differently to the same car without. 
    
    Bill.

    In order to maximise road safety, all cars must be designed to be as
    perceptibly dangerous as possible. There must be razor sharp metal
    edges in front of all occupants, no windows or doors to maximise
    contact with the elements, no instruments and no brakes. On the basis
    of some of the comments here, this should eliminate the majority of
    accidents and casualties. 
    
    Personally, I shall stick to automatic, ABS, good tyres, optimum
    primary safety, and within that optimum secondary precautions.
    
    Steve

a number of people have said that volvo drivers seem to be the worst offenders
when driving, thinking that they have a shark cage built around their tank etc
etc

but surely the worst offenders are van drivers, from dented metro BT vans upto
7.5 tonne trucks. They flash their hazards and do U turns on busy roads,
reverse blindly into busy roads etc etc...

I used to do similar things when I worked as a delivery driver, we had merc
307D's (loadsa metal) I was pretty sure that most vehicles under 5tonnes would
be worse off in any accident than myself. (FWIW 3 cars wrote themselves off on
that van; two of those when the van was safely,legally parked)

then the company changed to bedford midi type vans - they don't have much metal
in front of the cab - I took MUCH more care when driving that.

having said that, it all happened when I was a young 'un & my driving attitude
has matured greatly since then! (although it's still pay-back time when I get to
drive the 7.5 tonne truck :-)


...art_ever_cautious_in_the_weakly_defended_r5

    >> "Nationally, more people are injured in horse riding accidents than
    motorbikes,
    
    How many motorbikes do you see riding horses?  :^)

>	Everybody thinks driving a motorbike is extremely dangerous
> i.e. very high percieved risk, but its a lot safer than horse riding

Having done both....this is a dubious statement !

I think you will find that, over an equivalent period, many more people are 
killed riding a motorbike than riding  a horse; and certainly there are a far 
greater proportion of serious injury from crashing motorbikes than falling off 
a horse (it's difficult to "crash" a horse :-))  You get more brain damage and 
other impact injuries from motorbikes, you would almost never find that you 
would need a limb amputating after a horse gets the better of you !

    Ah , but they havn't yet invented ABS for the horse. Therefore that 
    statement is probably true. NO ABS makes the horse more dangerous than
    the motorbike with it fitted.
    
    Garry

    Ah, but horses do have four leg drive, and an on-board computer with
    optical and aural obstacle detection, which more than makes up for the
    lack of ABS.
    
    Steve 

Yes, but amazingly low power, only 1 BHP.


Simon

    For your info, Yamaha has now announced and is selling their FJ1200
    with ABS. There was a review of it in M/C News and the test rider drove
    an ABS equipped bike at the TRRL in Crowthorne.
    He said that it was very good and on a wet and oily road surface, at
    60MPH he stopped very quickly and upright.
    
    I recently fell off my bike on a straight greasy road at 60MPH while
    trying to avoid a taxi that had pulled out on me. I stopped quite
    quickly but in the process I ruined some waterproofs and a �100 crash
    helmet... plus �120 worth of repairs to my bike just to get it
    roadworthy again ( the bike didn't stop quite as quickly as me ).
    
    When it comes to the crunch (excuse the pun) there are situations where
    ABS _WILL_ save lives. In my recent escapade, I know I would have
    preferred to give ABS the chance to do the trick.
    
    James

    
    Been away, so missed wooden spoon until now ---
    
    
    Lots of choice for cars with ABS, so easy to rule out those without
    out. Only a difficulty in extreme cases -- like a couple of years back 
    when I decided not to have an Integrale. Painful decision.
    
    Very little choice on motorcycles - wish Laverda & Ducati had it, but
    they don't. As it happens I'm a born coward on motorcycles - have had
    them for over 30 years, raced them , done all sorts of things --- but I
    treat them with great (& increasing) respect. 100 bhp through a little
    bit of unstable rubber means that your road sensitivity & forward
    thinking is highly tuned -- but, you can still get caught out by the
    entirely unpredictable.

    ABS is only available on BMW, Yamaha and most Russian makes (no matter
    how hard you brake, the drum brakes will never block! ;-) ).
    
    I feel that ABS on bikes serve the same purpose as boots, leathers,
    lids; they give additional safety, but most of all a 'comfy' feel of
    safety. Thus your brain will allow you to take more risk.
    I know the limitations of my Guzzi LeMans, know how it feels to go down
    and ride accordingly. Technology will never replace competent driving.
    
    Back to my Polo..........
    Flying Dutchman

Driving along our country lanes last night I had a bit of a nasty
experience.  A car appeared coming the other way so I moved over a bit
(left two wheels on the gravel) and thought I'd slow down by pressing
the middle pedal.  So I did and nothing happened, the car continued
to carry on at the same speed with lots of clunking noises coming from
the wheels.

Does this mean that if ABS detects one wheel is locked it will unlock
it and the other wheel (assuming dual independent diagonal braking
circuits) ?  Because this is what appeared to happen.  If so, there's
certainly room for improvement in the area of ABS.

tp

	Trevor, I think that's exactly what happens.  What do you expect?
	If only one side of the car had any braking then you'd have spun
	(in extreme circumstances).  My favourite quote came from someone with
	abs who hit the car in front after braking on snow "It didn't work".
	Well, it did, but not in the way he expected.

	Dave

    I do lots of driving on narrow lanes.  The small stones that wash out
    of the banks often makes them as slippery as ice.  I find that ABS does
    do the right things - the stones are not just under the left wheels,
    they are spread very finely (by people with the left wheels in the bank
    :-)
    
    Jc

    When one wheel begins to lock up the ABS comes into action and releases
    that brake (only). Assume it is a front wheel that is doing this.
    You now have a situation where you have lost most of your braking on
    that side of the car. The car will want to turn, as the brakes on the
    other side are still in action. On a good road surface this is probably
    not going to cause trouble, but on a loose surface the extra forces
    will break the grip of some other wheel on the surface, and the car
    will start to rotate - at least it would if you didn't have ABS. As
    soon as the other wheel loses grip the ABS will release the brake on
    that wheel as well, the wheel will regain grip and will be able to keep
    you heading in the intended direction (although it wont have much
    stopping power). Of course the brakes get reapplied as soon as the
    wheel starts rotating again, and the average braking effort is just
    about as much as you can get from a loose surface (I.e. not much).
    
    In general it is better to be able to steer the car than to get into an
    uncontrolled spin, although the stopping distance when travelling
    sideways on gravel (and other loose surfaces) is probably shorter than
    when travelling straight with ABS.
    
    Andrew

    
     I believe the Original (and perhaps later) Audi Quattro's were fitted
    with a switchable ABS, so that on surfaces such as Snow, Loose Gravel,
    Wet Leaves etc the wheels would lock allowing the Tyres to 'Bite
    through' to the road surface beneath - the theory being that it was
    better to do this than to carry on indefinitely....
    
     Incidentally, Staffordshire Police have ABS removed from all Traffic
    Patrol cars prior to delivery, and their drivers are taught how to
    Cadence(sp?) brake..... A friend who Is a Police driving Instructor
    for the Region has told me several Funny (and some not so funny)
    stories relating to this....
    
    Graham_whos_not_at_All_Sure_of_The_Benefits...
    

    Cadence braking involves taking advantage of the weight transfer when
    the nose goes down.  
    
    I made a motorcyclist v. nervous once, coming off the A3 outbound from
    London onto the ramp for the M25.  I had gone a bit faster than I
    should have (as one does) and found the queue on the ramp longer than
    expected.  This guy was right at the back...
    
    Screetch, screetch, screetch...
    
    Richard
    

	At least one person smashed his car on Sunday
by not spinning.
	ABS is not an excuse for controlling your
car. I think ABS should be left to the likes of Steve Soper,
And Joe punter should be made to learn how to control
his car under more conditions than on the pathetic car
test.
	A two part test for cars over 45 bhp.

	Second part to include braking in poor and
uneven conditions, Practice in spinning (YES learning 
how and when to spin! and 
recovery from getting it sideways)

    Every 3 years a refresher

	The ROSPA ADA, (Advanced Drivers Association), offers
	the best road driving instruction in the country. To
	remain a member you must re-take their examine every
	three years. (And it's *hard*).

	One option would be to get insurance companies to reduce
	premiums by a considerable amount for ROSPA qualified
	drivers. As far as I am aware, this does not happen.
	When I was a member, the best reductions I was offered
	by insurance companies were negated by higher base 
	premiums.

	Ian.

	More info:

		ROSPA ADA,
		Cannon House,
		The Priory,
		Queensway,
		Birmingham,
		B4 6BS.
		021-233 2461.

	Re: 116

	You'd be surprised how many drivers under estimate
	their ability to learn behind the wheel. A little
	instruction can go a long way!

	Mind you, it never ceases to amaze me how many drivers
	over estimate their ability :-)
	
	Re: 117

	I'm currently waiting to get the "new" list of Insurance
	discounts offered to RoSPA members. 

	Some of the discount are scaled according to the grade
	of pass you have. (Gold's can get you 20% discount).

	Graham

    When I did my "drive and survive" a couple of years back I asked the
    guy (ex motorway cop) what he thought about ABS. He said he personally
    wasn't a fan on two counts, firstly because he reckoned that many ABS
    systems simply weren't good enough (cadence rate too slow), and
    secondly because of the complacency factor ("I can stop fast, so I
    don't have to worry about getting into dangerous situations").
    
    Just reporting his opinion....!
    
    I've heard the latter argument used by the anti-seatbelt lobby too. I
    even heard a theory once that the legislation that would guarantee a
    drop in accidents would be to ban seatbelts entirely but require all
    cars to have a 6 inch sharpened steel spike in the centre of their
    steering wheels.
     

	ABS stories, #192.

	I was going around a large roundabout here in Brussels
	a couple of weeks ago when another car came straight out 
	in front of me. 

	The ABS did two things for me:

		1. It gave me the confidence to apply heavy 
		   braking, even though the road was wet.
		   I felt the ABS working and realised at the
		   time that without it a locked nearside front
		   wheel was more than a possibility.

		2. It allowed me to concentrate on the steering
		   and hence avoid him and other road users.

	I vote for.

	Ian.
		      

    Re skidding and spinning in the driving test. In 20 years of driving I
    have never been in an uncontrolled spin or skid. I like to think this
    is not because I'm a good driver, I'm not (3 accidents) but because I
    have some empathy with the state of the road on which I'm driving. I
    would suggest that for 99% of motorists skid control is a waste of
    time. Now "defensive/sympathetic..." driving is another matter. The
    driving test concentrates on the mechanics of driving and not at all on
    the attitudes and etiquette of motoring.
    
    Andrew

    
    RE:learning to drive in slippery conditions
    
    Well it wasn't a test requirement but I learned to drive with a small
    independant driving school during the winter and I'd only had 4 or 5
    lessons when down came the snow I assumed my lesson would be canceled,
    but the guy duly arrived on time, I assumed he'd come to tell me it was
    cancelled. His attitude was, well your going to have to drive on the
    stuff sometime, it may as well be now with me there to instruct you and
    the luxury of dual control! So of we went into the snow, and he told me
    the right way to stay in/re-gain control and the wrong way and we went
    and tried them to show the difference, then practised the right way.
    
    We in the uk. are too frightened of snow/slippery surfaces (yes that is
    a gross-generalisation 8*) ) I personally am not frightened of driving in
    snow....don't get me wrong I have a great deal of respect for the stuff
    and I would reduce my speed and drive very cautiously, but it wouldn't
    stop me driving and making reasonable progress (a lot of drivers over
    react and traffic grinds to a standstill)
    Now what I am frightened of is black Ice.....that stuff is bad news,
    and I've been there I'd already done 20 miles of a 30 mile journey, you
    can tell when the road is a bit slippery, without sliding all-over you
    can feel that the car is a bit twitchy......well not a sign of that in
    20 miles then all of a sudden sheet ice the full width of the road for
    about 50 feet and you can't see it you don't know it's there till your
    on it. At 50mph you don't stand a chance! The Police described it as an
    accident waiting to happen.
    The other thing on the roads that terrifies me is....people who drive
    at unearthly speeds in snow and fog .......your doing 40 and
    concentrating for all your worth...thinking could I stop in time if
    there was stationary traffic just out of my vision and you come up with
    the answer......MAYBE, when some looney comes past you at 70-80 and you
    think that guy can't see any more than I can..what is he on! it must be
    like driving blindfold!

    What's the latest thinking on ABS?
    
    On my current Calibra I find it annoying, it sometimes kicks
    in when braking heavily on a bumpy service.
    
    However, I reckon if it ever saved your life, or got you 
    out of a tight spot, it would be worth it!
    
    Any theories, thoughts etc much appreciated!
    
    If it was a cost option on your car, would you buy it or not?
    
    Greg

    On my Cavalier which I have just returned, I too found that the ABS was
    too sensitive, and that on any uneven surface (lots of cobbled streets
    here!) would result in a distinct lack of confidence in braking.  So I
    guess it was super safe!
    
    My current Omega seems much less sensitive, but on the one occasion I
    needed it ( to steer around a wayward pedestrian who ran into the
    road without looking) worked a treat.
    
    I suppose that it depends on the specific implementation.  
    
    I would probably pay extra if it was optional, and didn't frighten me
    like the Cavalier did.  An off switch would be nice for when you drive
    down cobbled or uneven roads, but would one always remember to use it.
    
    That's my two penn'orth anyway
    
    - Chris -