Correct Braking Proceedure

Jon Senior said:

Think how far back from the front contact point you have to be in
order to not go over the bars. You need to be most of the distance
behind the rear contact point in order to keep the weight on the rear
wheel. How long are your arms?

Hence my "Mr Tickle" jibe, but no-one noticed or got that :-( :-)

~PB

Response to Pete Biggs:

Quoted message said:

Hence my "Mr Tickle" jibe, but no-one noticed or got that :-( :-)

<notices> Snuk!

I think my brain usually automatically filters out people's "so-and-so
wrote" lines, as it does with sigs. Consider that a SMIDSYJ. ;-)

--
Mark, UK

"I don't mind people looking down on me as long as they don't expect me
to be looking up."

On Wed, 26 Oct 2005 15:33:37 +0100, "Pete Biggs"
<[email hidden]> said in
<[email hidden]>:

Quoted message said:

Quoted message said:

My experience is the rear brake is good for balancing the bike during
braking, esp on loose off-road corners, and for testing traction on
slippery surfaces but if you are braking in slippery conditions and
you use the back brake to brake, it will lock very easily at which
point the back will skid round on you. So IME the back brake is
something to be very wary of in slippery conditions and of little use
in dry conditions.

Quoted message said:

But a front tyre skid is harder to recover from, especially on a bend*.
The rear brake is useful when that is a serious risk, be it together with
the front or on its own, depending on the situation.

I dispute this. I can't remember the last time I braked hard enough
to get a front wheel skid (I'm not sure I ever have), but I have often
skidded out the rear even when braking relatively gently.

Guy
--
http://www.chapmancentral.co.uk

"To every complex problem there is a solution which is
simple, neat and wrong" - HL Mencken

Been cycling for about 53 years and it has never ocurred to me once
that there might be a "Correct Braking Proceedure". Basically you
brake when you need to slow down and in emergencies you brake hard with
both brakes. What else is there to say (ignoring the 63 messages
preceding this)? How would you distribute braking 50/50 or 75/25 etc -
total bollocks!! What about 93/7 % which is my preferred front/rear
distribution of force! I recommend it - don't bother with 90/10 its a
waste of time.
just bin dahn the boozer

cheers

Jacob

Quoted message said:

Been cycling for about 53 years and it has never ocurred to me once
that there might be a "Correct Braking Proceedure". Basically you
brake when you need to slow down and in emergencies you brake hard with
both brakes. What else is there to say (ignoring the 63 messages
preceding this)? How would you distribute braking 50/50 or 75/25 etc -
total bollocks!! What about 93/7 % which is my preferred front/rear
distribution of force! I recommend it - don't bother with 90/10 its a
waste of time.
just bin dahn the boozer

Naaa, really? :-) ;-)

But you're not wrong. It's a symptom of the modern age, though, innit?
Can't do fsck all without training, a hazard review, a report, further
training, certification, and a health and safety review. What ever
became of suck it and see? Or, in this case suck it and end up under
a bus? ;-)

--
Nobby

Just zis Guy said:

On Wed, 26 Oct 2005 15:33:37 +0100, "Pete Biggs"
<[email hidden]> said in
<[email hidden]>:

Quoted message said:

Quoted message said:

My experience is the rear brake is good for balancing the bike during
braking, esp on loose off-road corners, and for testing traction on
slippery surfaces but if you are braking in slippery conditions and
you use the back brake to brake, it will lock very easily at which
point the back will skid round on you. So IME the back brake is
something to be very wary of in slippery conditions and of little use
in dry conditions.

Quoted message said:

But a front tyre skid is harder to recover from, especially on a bend*.
The rear brake is useful when that is a serious risk, be it together with
the front or on its own, depending on the situation.

I dispute this. I can't remember the last time I braked hard enough
to get a front wheel skid (I'm not sure I ever have), but I have often
skidded out the rear even when braking relatively gently.

I've done it once, well twice really in the same event. Descending into
Llanthony valley from Hay on Wye at about 40mph approaching a cattle
grid and then a right hand bend. I braked and the front and rear wheels
locked, I let the brakes off and braked again with the same effect (and
in the split second congratulated my self on not falling off) then I had
to stop braking due to the cattle grid. Over that I leant into the bend
which I was never going to get round. I went up the bank and thought I
was going to get very familiar with the barbed wire fence I could now
see but was able to ride along the top of the bank until the front wheel
dropped into a hole and I came to a sudden halt, still up right. Then I
remembered I had tightened the toe straps and with cleated shoes I could
not get my feet out.

Toppled onto the road still with my feet in the pedals.

When I got back to the camp site and before any one knew I had taken a
tumble one of the locals said: "You need to be careful on the road as
the dust from the earth is really slippy in the dry". He was not wrong.

--chris

Just zis Guy said:

On Wed, 26 Oct 2005 15:33:37 +0100, "Pete Biggs"
<[email hidden]> said in
<[email hidden]>:

Quoted message said:

Quoted message said:

My experience is the rear brake is good for balancing the bike during
braking, esp on loose off-road corners, and for testing traction on
slippery surfaces but if you are braking in slippery conditions and
you use the back brake to brake, it will lock very easily at which
point the back will skid round on you. So IME the back brake is
something to be very wary of in slippery conditions and of little use
in dry conditions.

Quoted message said:

But a front tyre skid is harder to recover from, especially on a bend*.
The rear brake is useful when that is a serious risk, be it together with
the front or on its own, depending on the situation.

I dispute this. I can't remember the last time I braked hard enough
to get a front wheel skid (I'm not sure I ever have),

Have you ever cycled on ice?

Quoted message said:

but I have often skidded out the rear even when braking relatively
gently.

That happens even on the anti-skid road surfaces near the stop-lights,
when the car driver in front has the misbelief that yellow light means
"slam the brakes".

--
Måns Rullgård
[email hidden]

Just zis Guy said:

On Wed, 26 Oct 2005 15:33:37 +0100, "Pete Biggs"
<[email hidden]> said in
<[email hidden]>:

Quoted message said:

Quoted message said:

My experience is the rear brake is good for balancing the bike during
braking, esp on loose off-road corners, and for testing traction on
slippery surfaces but if you are braking in slippery conditions and
you use the back brake to brake, it will lock very easily at which
point the back will skid round on you. So IME the back brake is
something to be very wary of in slippery conditions and of little use
in dry conditions.

Quoted message said:

But a front tyre skid is harder to recover from, especially on a bend*.
The rear brake is useful when that is a serious risk, be it together with
the front or on its own, depending on the situation.

I dispute this. I can't remember the last time I braked hard enough
to get a front wheel skid (I'm not sure I ever have), but I have often
skidded out the rear even when braking relatively gently.

Never deliberately. A few times on ice or diesel. I seem to have a
reasonable sense of balance as I have managed to slide both wheels
before and stay upright..

Following many interesting and formative experiences as a child cyclist
(one game was seeing how big a stoppie you could do and not go over the
bars) with dented chrome rims, I find it very hard to brake at maximum,
irrespective of the mode of transport. I did however pull my first
stoppie ever on my road bike (after fifteen years) when some numpty
turned right almost through me (report passim, easter time) but didn't
slide the front wheel.

...d

"Saxman" <john.h.williams(removethis)@btinternet.com> wrote in message
news:[email hidden]...

Quoted message said:

Rich said:

If you haven't hit the brick wall yet, you're doing it right. Stop
worrying.

I have injured myself on a couple of occasions, one meant four stitches in
my upper lip, which wasn't pleasant!

Both incidents were nothing to do with braking, they were to do with not
looking (lack of concentration).

I might have the best brakes in the world, but I'm afraid not the best
brain!

So stop worrying about braking and get a new brain. The pain should have
helped!

Just zis Guy said:

Quoted message said:

But a front tyre skid is harder to recover from, especially on a
bend*. The rear brake is useful when that is a serious risk, be it
together with the front or on its own, depending on the situation.

I dispute this.

I maintain that it's harder to recover from a front wheel skid than a
rear. I don't dispute that rear skids are more common or that you can
loose control when the rear skids, but nearly all rear skids are no big
deal. A front skid that lasts more than a brief moment is a very serious
deal indeed if the bike is leant over at the time, but on the straight as
well if it is very slippery.

Quoted message said:

I can't remember the last time I braked hard enough
to get a front wheel skid (I'm not sure I ever have), but I have often
skidded out the rear even when braking relatively gently.

My flabber is gasted. Perhaps you missed my point about dodgy surfaces?
I would have thought most cyclists have skidded the front tyre from
over-enthusiastic braking. I do include gravely, oily and icy surfaces.
Note that I exclude clean dry tarmac on the straight. (I'll also leave
out recumbents in case it's any different for them).

I'll never forget front-braking and slipping over at the end of a frosty
platform while I rushed to catch a train. Ok I shouldn't have been
cycling on the platform but the goods van was at the wrong end of the
train! :-)

And I've got a feeling I might have been front-braking while turning on my
last accident (last ever, I like to think) where I slipped over, although
I'm not sure if I was -- but this worry has made me much more careful
about where and how I do/don't front-brake (and corner and ride in
general).

There is always the danger of the road having a small patch of loose or
slippery material even when it basically looks ok. Gaps/reservations
between lanes at fork junctions and the like is a classic place for dusty
stuff, for example.
Front-braking is dangerous when off-line at those sort of places. Edges
of T-junctions at the end of lightly used roads is another dodgy one.

~PB

Pete Biggs said:

My flabber is gasted. Perhaps you missed my point about dodgy surfaces?
I would have thought most cyclists have skidded the front tyre from
over-enthusiastic braking. I do include gravely, oily and icy surfaces.
Note that I exclude clean dry tarmac on the straight. (I'll also leave
out recumbents in case it's any different for them).

I've temporarily lost the front wheel on a number of occasions, but only
once due to bad braking (On a corner, on a speed bump, in the wet!).
I've learnt what line to take to avoid touching the little metal
pyramids that Edinburgh council use to mark pedestrian crossings. They
frequently caused me to skip sideways with which ever wheel touched them.

Jon

On Wed, 26 Oct 2005 23:31:21 +0100, Måns Rullgård <[email hidden]>
said in <[email hidden]>:

Quoted message said:

Quoted message said:

Quoted message said:

> My experience is the rear brake is good for balancing the bike during
> braking, esp on loose off-road corners, and for testing traction on
> slippery surfaces but if you are braking in slippery conditions and
> you use the back brake to brake, it will lock very easily at which
> point the back will skid round on you. So IME the back brake is
> something to be very wary of in slippery conditions and of little use
> in dry conditions.

Quoted message said:

Quoted message said:

Quoted message said:

But a front tyre skid is harder to recover from, especially on a bend*.
The rear brake is useful when that is a serious risk, be it together with
the front or on its own, depending on the situation.

Quoted message said:

Quoted message said:

I dispute this. I can't remember the last time I braked hard enough
to get a front wheel skid (I'm not sure I ever have),

Quoted message said:

Have you ever cycled on ice?

Yes. I have had both wheels go out from under me, but never had a
front wheel skid in braking.

Guy
--
http://www.chapmancentral.co.uk

"To every complex problem there is a solution which is
simple, neat and wrong" - HL Mencken

On Thu, 27 Oct 2005 00:45:22 +0100, "Pete Biggs"
<[email hidden]> said in
<[email hidden]>:

Quoted message said:

Quoted message said:

Quoted message said:

But a front tyre skid is harder to recover from, especially on a
bend*. The rear brake is useful when that is a serious risk, be it
together with the front or on its own, depending on the situation.

Quoted message said:

Quoted message said:

I dispute this.

Quoted message said:

I maintain that it's harder to recover from a front wheel skid than a
rear. I don't dispute that rear skids are more common or that you can
loose control when the rear skids, but nearly all rear skids are no big
deal. A front skid that lasts more than a brief moment is a very serious
deal indeed if the bike is leant over at the time, but on the straight as
well if it is very slippery.

Yes, my bad. What I mean is I dispute that the front wheel skid is
sufficiently common to be a cause of concern in the way you describe.

Quoted message said:

Quoted message said:

I can't remember the last time I braked hard enough
to get a front wheel skid (I'm not sure I ever have), but I have often
skidded out the rear even when braking relatively gently.

Quoted message said:

My flabber is gasted. Perhaps you missed my point about dodgy surfaces?

Nope. I just can't think of a situation where the front wheel would
skid and braking with the rear would do anything at all. Either there
is enough traction to brake, or there isn't. I am an every day
cyclist and I have ridden a recumbent bike fitted with slicks in snow
and ice, I have experienced slippery surfaces, and I've lost the bike
a couple of ties when there was no grip whatsoever, but no braking
with either wheel was ever going to work in that case.

Quoted message said:

I would have thought most cyclists have skidded the front tyre from
over-enthusiastic braking.

Not that I can recall. I don't usually use the brakes at all in those
kind of conditions.

Advising people to rear brake in slippery conditions sounds to me akin
to advising people not to wear seat belts so they will be thrown clear
in a rollover. Not only is the failure condition rare, I can see how
the supposed fix might cause problems of its own.

Guy
--
http://www.chapmancentral.co.uk

"To every complex problem there is a solution which is
simple, neat and wrong" - HL Mencken

Pete Biggs said:

My flabber is gasted. Perhaps you missed my point about dodgy
surfaces? I would have thought most cyclists have skidded the front
tyre from over-enthusiastic braking. I do include gravely, oily and
icy surfaces. Note that I exclude clean dry tarmac on the straight.
(I'll also leave out recumbents in case it's any different for them).

It isn't. If the front wheel loses grip for any reason, the chances of
coming to a standstill minus a certain quantity of skin is this: high.

How to do it: url:http://www.bhpc.org.uk/photos/eastway_agm_05/08.jpg
How /not/ to do it: url:http://www.bhpc.org.uk/photos/eastway_agm_05/68.jpg

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
Jack Hackett for Pope, next time!

Just zis Guy said:

Not that I can recall. I don't usually use the brakes at all in those
kind of conditions.

Advising people to rear brake in slippery conditions sounds to me akin
to advising people not to wear seat belts so they will be thrown clear
in a rollover. Not only is the failure condition rare, I can see how
the supposed fix might cause problems of its own.

I do a lot of off-road riding and the one thing braking on the back in
very slippery conditions does is to bring the back wheel round on you
big time. One of the big advantages of hydraulic discs is the
modulation is superb so you can continually test grip in slippery
conditions by taking the back wheel just to sliding point and backing of
a tad just as you can on-road on a fixed.

--
Tony

"I did make a mistake once - I thought I'd made a mistake but I hadn't"
Anon

Just zis Guy said:

Nope. I just can't think of a situation where the front wheel would
skid and braking with the rear would do anything at all.

BTDTGTTS. Studded tyres on ice[1]. On uneven ice. Can somewhat
unhappily slide the front. Similar thing with the plenty of wet leaf
mush on the roads at present. Possible to get reasonable rear wheel
braking whilst losing the front wheel. Again, BTDTGTTS.

...d

[1] The real stuff. NOT a heavy frost.

Just zis Guy said:

What I mean is I dispute that the front wheel skid is
sufficiently common to be a cause of concern in the way you describe.

It doesn't need to happen often for it to be a serious problem. One
serious injury is more than enough for a lifetime.

Quoted message said:

Quoted message said:

Quoted message said:

I can't remember the last time I braked hard enough
to get a front wheel skid (I'm not sure I ever have), but I have
often skidded out the rear even when braking relatively gently.

Quoted message said:

My flabber is gasted. Perhaps you missed my point about dodgy
surfaces?

Nope. I just can't think of a situation where the front wheel would
skid and braking with the rear would do anything at all. Either there
is enough traction to brake, or there isn't.

1) You can't always be certain how much traction there will be. The most
common situation to use the rear brake alone is where the front wheel
MIGHT skid and could easily make you fall. The fact that the front wheel
PROBABLY won't skid means the rear brake probably WILL do something
without skidding, but if it did skid it would be less catastrophic.

2) The bike would often slow down a bit before the skid (skids not
starting absolutely instantly), and also from teh skid somewhat,
especially in a straight line. Rear skidding is slower than frewheeling.
It's dangerous but less dangerous than skidding the front because you can
more often recover from it without falling.

Ok, you won't need to do this if you're a perfect cyclist in a perfect
world. Well, I'm not, so I do: most often when I've made a misjudgement
about the speed to use. There are times when it's better than the
alternative of hitting something, or running off the side of the road or
leaning more to corner more tightly or swerve.

Quoted message said:

Advising people to rear brake in slippery conditions sounds to me akin
to advising people not to wear seat belts so they will be thrown clear
in a rollover. Not only is the failure condition rare, I can see how
the supposed fix might cause problems of its own.

It might but it's often the lesser of two evils. ~PB

From http://www.sheldonbrown.com/brakturn.html#rearuse :

"When to Use The Rear Brake

"Skilled cyclists use the front brake alone probably 95% of the time, but
there are instances when the rear brake is preferred:

"Slippery surfaces. On good, dry pavement, it is generally impossible to
skid the front wheel by braking. On slippery surfaces, however it is
possible to do so. It is nearly impossible to recover from a front wheel
skid, so if there is a high risk of skidding, you're better off
controlling your speed with the rear brake.

"Bumpy surfaces. On rough surfaces, your wheels may actually bounce up
into the air. If there is a chance of this, don't use the front brake. If
you apply the front brake while the wheel is airborne, it will stop, and
coming down on a stopped front wheel is a Very Bad Thing.

"Front flat. If you have tire blowout or a sudden flat on the front wheel,
you should use the rear brake alone to bring yourself to a safe stop.
Braking a wheel that has a deflated tire can cause the tire to come off
the rim, and is likely to cause a crash.

"Broken cable...or other failure of the front brake.

"Long mountain descents, when your front brake hand may get tired, or you
may be at risk of overheating a rim and blowing a tire. For this
situation, it is best to alternate between the front and rear brake, but
not to use them both at once."

I submit that on or about Thu, 27 Oct 2005 13:14:03 +0100, the person
known to the court as "Pete Biggs"
<[email hidden]> made a statement
(<[email hidden]> in Your Honour's bundle) to the
following effect:

Quoted message said:

Quoted message said:

What I mean is I dispute that the front wheel skid is
sufficiently common to be a cause of concern in the way you describe.

It doesn't need to happen often for it to be a serious problem. One
serious injury is more than enough for a lifetime.

Sounds to me like the fallacy of misleading vividness.

Guy
--
http://www.chapmancentral.co.uk

"To every complex problem there is a solution which is
simple, neat and wrong" - HL Mencken

Bertie Wiggins cycling_remove_bertie@yahoo_dot_co_dot_uk said:

On 25 Oct 2005 18:52:44 -0700, "James Annan"
<[email hidden]> wrote:

Quoted message said:

Quoted message said:

I repeat: it is a matter of elementary geometry and mechanics. If you
can't do it, stop pretending that you know better than those of us who
can!

Quoted message said:

I am not so arrogant as to insist that I am correct; I am not so
conceited as to claim superior mathematical, geometric or mechanical
knowledge. However, I am not going to accept, on your word, that
applying the front brake alone is more effective than applying front
and rear brake together. As the geometry and mechanics is so
"elementary" you may provide a mathematical model to support your
claim, if I cannot follow the "elementary" mathematics I am sure
others can.

It's a very simple triangle of forces model. When braking forces act
on the CofG of bike and rider, gravity downwards, and inertial
response to the deceleration forwards. This shifts the direction of
the resultant force forwards towards the front wheel. When the
direction of the resultant force passes through the front wheel
contact patch the back wheel will lift up in the air and you'll go
over the handlebars.

So the interesting question is whether the front brake alone can
provide enough braking to do this. Sadly, if you work it out, the
answer is yes, at substantially below the maximum braking force than
can be expected from rubber tyres on a dry road. In other words,
compared to cars and motorcycles, the geometry of pedal bicycle weight
distribution limits them to pathetic emergency braking.

A corollary of this is that there's no point in using the back brake
in hard braking on a dry road, unless you're going up a steep hill at
the time. Not only no point, but worse than useless, because you'll
end up trying to control a rear wheel skid at significantly less than
maximum braking.

This is not advanced maths. Galileo could have done it, and if we had
decent schoools and schoolteachers the average teenage schoolkid would
be able to work it out from first principles.

All this balanced compromise and efficiency stuff you've been talking
about is true, but irrelevant, because the seriously limiting maximum
case of rear wheel lift renders them all inoperable.

--
Chris Malcolm [email hidden] +44 (0)131 651 3445 DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
[http://www.dai.ed.ac.uk/homes/cam/]

In message <[email hidden]>

Chris Malcolm said:

A corollary of this is that there's no point in using the back brake
in hard braking on a dry road, unless you're going up a steep hill at
the time. Not only no point, but worse than useless, because you'll
end up trying to control a rear wheel skid at significantly less than
maximum braking.

I would argue that using the rear brake for at least a small amount of
braking is good for safety. If you brake at 90%/10% front back, then
if the the back lifts up, it will just skid, you can regain control and
carry on braking.

If you are on 100% front, and the back lifts a touch, you will go over
the handlebars before you can react. (The higher the rear wheel, the higher
the CoM, and thus increased torque on the front wheel to flip you over.)
i.e. positive feedback.

Martin.

--
Typed by monkey #27662472869676 on typewriter #7552416572242
When emailing me, please include the word Banana in the subject line.