On Mon, 21 Jun 2004 19:01:34 +0100, JohnB wrote in
message :

I thought it was BeHit who put 25000 children into containers.

Tee-hee! :-)

From the **** Happens department - BeHIT keep saying that cycling is a
leading source of death and head injury in children, but:

- over twice as many children die from congenital abnormalities as
from cycling
- more children die of leukaemia than from cycling
- more children die following assault than a cycle crash
- more children die from asthma and other respiratory diseases than
from cycling
- over twice as many children die of brain cancer than cycling head
injuries.
- as many children die of menigitis as of cycling head injuries.

http://www.statistics.gov.uk/STATBAS...eets/D8257.xls

Guy
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On Mon, 21 Jun 2004 17:57:44 GMT, Velvet
wrote in message :

I think we're kindof in agreement here. My point was that people aren't
all that likely to be braking as well as ABS would if you apply it
properly - people (myself included) either tend to overbrake (and skid
if no abs) or underbrake (abs or no, they'll not stop as fast as if they
overbraked with abs).

Indeed. That was my point: what ABS is doing is compensating for poor
technique, not helping you "stop quicker".

I don't drive any closer (or further away, it has to be said) than
pre-ABS.

You think. But on average, people do. That's what risk compensation
is about. It's pretty widespread - see Tony's comment re "childproof"
containers above.

Or read Risk - it's very interesting.

Guy
--
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88% of helmet statistics are made up, 65% of them at Washington University

On Mon, 21 Jun 2004 09:43:35 GMT, "Richard J."
wrote (more or less):

Just zis Guy, you know? wrote:

I don't rely on ABS to stop me quicker - I
use it to even out the fact that the car in front probably has it
and will stop quicker than I can if I don't have it...

If you are relying on ABS to stop you, you are driving too close to the
vehicle in front.

Er, actually ABS doesn't really affect stopping distances. It
allows you to steer while braking.

Er, have you driven on snow with and without ABS? It certainly does
affect stopping distance on ice or snow.

And in different ways.

On ice, it will prevent lock-up of each wheel, increasing braking
efficiency across the four wheels, decreasing stopping distance
compared to a manually-controlled wheel.

On snow, locking up the wheels can have the beneficial effect of
causing a wedge of snow to build up in front of the locked wheel,
which decreases stopping distance on snow compared to an abs wheel.


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Euan
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On Mon, 21 Jun 2004 09:43:35 GMT, "Richard J."
wrote (more or less):

Gawnsoft wrote:
On Sun, 20 Jun 2004 20:08:54 GMT, "Richard J."
wrote (more or less):

Paul Dicken wrote:
Mention of Mayer Hillman reminded me of a view he expressed in a
meeting I attended. He suggested all car bumpers should be made of
glass and drivers seated on them. His view was that standards of
driving will go up immediately.

... because people driving in a vulnerable vehicle would drive more
safely?

There is a big difference between 'more safely' and 'absolutely
safely'.

People drive less safely with seatbelts than they do without
seatbelts == People drive more safely without seatbelts than they
do with seatbelts. people never have accidents when driving
without a seatbelt.

Are you
suggesting that we should abandon seat belts in order that we should
drive more safely?
....
Well, severity of accident is part of the safety equation. My point was
that before seat belts were introduced, there were very many disastrous
accidents because many people *didn't* drive safely enough to avoid
being thrown through the windscreen.

And people drive /less/ safely than that now. It's just that a great
deal of the risk has been transferred to others.

Overall, driving with belts is
safer than it used to be, i.e. it kills fewer people.

Is, perhaps counter-intuitively to you, not true.

I assume that means "not that"; please write in English.

To be exact, it means 'is not equal to'. But your inference in
context works perfectly well.

I'll continue to use arithmetic and logic symbols in my posts.

--
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Euan
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On Mon, 21 Jun 2004 07:08:11 GMT, "Orienteer"
wrote (more or less):
....
Bit of a myth that ABS enables a vehicle to stop quicker, in fact it can
have the opposite effect.

Only on loose surfaces like snow or gravel.

On clean dry surfaces a car with independent ABS per wheel can stop
faster than a non-abs car (which will likely skid under extreme
braking), and gains the controllability advantage of cadence-braking
without having to stop braking all four wheels, which a non-abs car
has to do to effect cadence braking.

It's purpose is to enable the vehicle to be
steered while braking hard, which without ABS often results in a skid and
loss of control.

A skid also results in longer braking distances.





--
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Euan
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Just zis Guy, you know? wrote:
On Mon, 21 Jun 2004 17:57:44 GMT, Velvet
wrote in message :


I think we're kindof in agreement here. My point was that people aren't
all that likely to be braking as well as ABS would if you apply it
properly - people (myself included) either tend to overbrake (and skid
if no abs) or underbrake (abs or no, they'll not stop as fast as if they
overbraked with abs).


Indeed. That was my point: what ABS is doing is compensating for poor
technique, not helping you "stop quicker".

Whether it compensates for my technique or not is immaterial, in the
same given circumstance, with ABS I will stop quicker, in a shorter
distance, than without ABS.



I don't drive any closer (or further away, it has to be said) than
pre-ABS.


You think. But on average, people do. That's what risk compensation
is about. It's pretty widespread - see Tony's comment re "childproof"
containers above.

If I remembered I actually had ABS more than once a few months then I
might believe I drive closer/faster. But given I don't, I doubt it has
any affect. To be honest, since I've never been in a situation where
tromping the brakes has actually activated the ABS, it seems likely that
I'm not compensating for the percieved increase in safety.


Or read Risk - it's very interesting.

Guy

I'm sure it's fascinating :-)

--


Velvet

On Mon, 21 Jun 2004 07:08:11 GMT,
Orienteer wrote:

Bit of a myth that ABS enables a vehicle to stop quicker, in fact it can
have the opposite effect. It's purpose is to enable the vehicle to be
steered while braking hard, which without ABS often results in a skid and
loss of control.

I don't have any figures for it but I suspect that when braking hard
from high speeds (70mph+) ABS may well enable a car to stop quicker.

Some (10+?) years ago there was an artical in SciAm about emergency
stops in cars at motorway speeds and it was suggested that the best bet
for the cars of the time might well be to deliberately skid.

IIRC stopping distances from these sorts of speeds when skidding were
about 20% further than the perfect stop. However, without ABS the
braking is split in a fixed percentage between back and front wheels.
The weight transfer to the front wheels can cause the rear wheels to
lock putting the car into a spin. By deliberately locking all the
wheels the car will stay pretty much in a straight line (motorways
don't tend to have enough camber to be likely to put a skidding car
into a spin.)

ABS eliminates this problem and allows maximum braking on the front
wheels.

But ABS doesn't have to be a good thing. The one time I have skidded
on the motorway I was very grateful for the noise. Picture the scene -
me on empty motorway, slip lane joining. Slow lorry almost at end of
slip lane that would be joining shortly after I had passed. Another
car on sliplane that would be joining about the same time as the
lorry. So I moved from lane 1 to lane 3 in order to give both vehicles
joining room to join without having to adjust their speeds. But the
car doesn't move into lane 2 to pass the lorry but continues into lane
3. Now I should have anticipated this but by the time I realised he
wasn't going to stay in lane 2 I was about level with his rear door
and going maybe 10mph faster. I didn't have time for the horn but my
squealing tyres meant he only came about 2 feet into lane 3.
(Skidding from 70mph to about 45mph leaves a big cloud of smoke!)

Tim.


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On Mon, 21 Jun 2004 19:59:49 +0000 (UTC), Tim Woodall
wrote in message
:

I don't have any figures for it but I suspect that when braking hard
from high speeds (70mph+) ABS may well enable a car to stop quicker.

I have only ever once managed to skid a car at 70, and that was a BX
with no ABS where the same hydraulics work the brakes and the
suspension. Weight transfer makes it quite hard to skid a car at 70.

Guy
--
May contain traces of irony. Contents liable to settle after posting.
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88% of helmet statistics are made up, 65% of them at Washington University

On Mon, 21 Jun 2004 19:55:05 GMT, Velvet
wrote in message :

Whether it compensates for my technique or not is immaterial, in the
same given circumstance, with ABS I will stop quicker, in a shorter
distance, than without ABS.

If you want to continue believing that "ABS stops you quicker" then be
my guest. But I refuse to indemnify you against any damage which may
result.

Angels dancing on the head of a pin notwithstanding, that is /not/
what it's designed for. Assuming that it is, will end in tears. As
the studies prove.

If I remembered I actually had ABS more than once a few months then I
might believe I drive closer/faster. But given I don't, I doubt it has
any affect. To be honest, since I've never been in a situation where
tromping the brakes has actually activated the ABS, it seems likely that
I'm not compensating for the percieved increase in safety.

So you say - now...

read Risk - it's very interesting.

I'm sure it's fascinating :-)

It is. Genuinely.

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

88% of helmet statistics are made up, 65% of them at Washington University

Just zis Guy, you know? wrote:
On Mon, 21 Jun 2004 19:55:05 GMT, Velvet
wrote in message :


Whether it compensates for my technique or not is immaterial, in the
same given circumstance, with ABS I will stop quicker, in a shorter
distance, than without ABS.


If you want to continue believing that "ABS stops you quicker" then be
my guest. But I refuse to indemnify you against any damage which may
result.

Look, I've explained how ABS could stop ME quicker, you'll note I've not
said it'll stop EVERYONE quicker.

Perhaps you overlooked that subtle point?


Angels dancing on the head of a pin notwithstanding, that is /not/
what it's designed for. Assuming that it is, will end in tears. As
the studies prove.

If I ever have cause to test it in that sort of situation then I'll find
out, won't I, one way or t'other.



If I remembered I actually had ABS more than once a few months then I
might believe I drive closer/faster. But given I don't, I doubt it has
any affect. To be honest, since I've never been in a situation where
tromping the brakes has actually activated the ABS, it seems likely that
I'm not compensating for the percieved increase in safety.


So you say - now...


read Risk - it's very interesting.


I'm sure it's fascinating :-)


It is. Genuinely.

Guy


--


Velvet