brake failure

"JG" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Whoops, that should have been, "a one tenth of one percent change in a
meter of cable/housing translates into 4mm+ of slop"...

Jobst, why would you "take" something I haven't said? is it what you
want to hear? What I wrote was "cable/housing". Whether its housing
compression, or housing seating, or cable unkinking, or cable
stretching, the point is simply that it takes a rather small amount to
have a noticable effect because of the 4:1 multiplier.

Jobst is trying to be exact I suppose but that's what tends to irritate
normal people who assume that there are normal errors in descriptions.

Quoted message said:

I "take" cable stretch to usually mean non-elastic
elongation - and accept that it is a real result of a number of
factors not including meaningful physical elongation of the cable
itself, which are a product of industry bike setup practices. As for
the cable's contribution to the overall elasticity of the braking
system, it's all bs until someone pulls out the micrometer...

You and I have more or less the same take on it. Absolute precision in
writing and meaning isn't really part of the internet experience.

JG said:

...

To tell the truth, I haven't paid much attention to what the two of
you are babbling about. It's just not as interesting as it was a
generation ago. I "take" cable stretch to usually mean non-elastic
elongation - and accept that it is a real result of a number of
factors not including meaningful physical elongation of the cable
itself, which are a product of industry bike setup practices. As for
the cable's contribution to the overall elasticity of the braking
system, it's all bs until someone pulls out the micrometer...

I may have missed it, but this thread rather quickly evolved into
something quite far the original post. It is no surprise, considering
everything that has been written since, but unless I just missed it, the
original poster hasn't been back!

JG said:

...

To tell the truth, I haven't paid much attention to what the two of
you are babbling about. It's just not as interesting as it was a
generation ago. I "take" cable stretch to usually mean non-elastic
elongation - and accept that it is a real result of a number of
factors not including meaningful physical elongation of the cable
itself, which are a product of industry bike setup practices. As for
the cable's contribution to the overall elasticity of the braking
system, it's all bs until someone pulls out the micrometer...

This thread rather quickly evolved into something quite far the original
post. It is no surprise, considering everything that has been written
since, but unless I just missed it, the original poster hasn't been back!

In article <[email hidden]>,

Tom Kunich' cyclintom@yahoo. com said:

"JG" <[email hidden]> wrote in message
news:[email hidden]
...

Quoted message said:

Whoops, that should have been, "a one tenth of one percent change
in a meter of cable/housing translates into 4mm+ of slop"...

Jobst, why would you "take" something I haven't said? is it what
you want to hear? What I wrote was "cable/housing". Whether its
housing compression, or housing seating, or cable unkinking, or
cable stretching, the point is simply that it takes a rather small
amount to have a noticable effect because of the 4:1 multiplier.

Jobst is trying to be exact I suppose but that's what tends to
irritate normal people who assume that there are normal errors in
descriptions.

Quoted message said:

I "take" cable stretch to usually mean non-elastic elongation - and
accept that it is a real result of a number of factors not
including meaningful physical elongation of the cable itself, which
are a product of industry bike setup practices. As for the cable's
contribution to the overall elasticity of the braking system, it's
all bs until someone pulls out the micrometer...

You and I have more or less the same take on it. Absolute precision
in writing and meaning isn't really part of the internet experience.

This is, however, a tech newsgroup and therefore there are some
expectations of accuracy and precision.

Quoted message said:

This is, however, a tech newsgroup and therefore there are some
expectations of accuracy and precision.- Hide quoted text -

To be precise and accurate, "some" means more than zero. There are
probably some expectations of accuracy and precision on
alt.garden.gnomes...

JG

In article
<[email hidden]>,

JG said:

Quoted message said:

This is, however, a tech newsgroup and therefore there are some
expectations of accuracy and precision.

To be precise and accurate, "some" means more than zero.

Indeed. Unfortunately in the context of my statement the degree of
accuracy and precision to be expected is not quantifiable. Nor was that
necessary for my intent, which simply to contradict Tom Kunich's
suggestion that accuracy and precision are alien to the Internet or to
Usenet. In this case your comment was directed more to precision than
accuracy.

catzz66 said:

This thread rather quickly evolved into something quite far the original
post. It is no surprise, considering everything that has been written
since, but unless I just missed it, the original poster hasn't been back!

No, Marian has been back - check May 23rd, for example. And she's been
updating her journal on Crazyguyonabike.com too. It's a great story so
far. She doubled back to a bike shop to get repairs, then got new
brake shoes, eventually. She's also met and socialized with a half
dozen bike clubs so far.

"Tim McNamara" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

In article
<[email hidden]>,

JG said:

Quoted message said:

This is, however, a tech newsgroup and therefore there are some
expectations of accuracy and precision.

To be precise and accurate, "some" means more than zero.

Indeed. Unfortunately in the context of my statement the degree of
accuracy and precision to be expected is not quantifiable. Nor was that
necessary for my intent, which simply to contradict Tom Kunich's
suggestion that accuracy and precision are alien to the Internet or to
Usenet. In this case your comment was directed more to precision than
accuracy.

Sorry if you don't understand English Tim but the fact remains that most
people are quite satisfied with normal accuracy and precision. Jobst and a
few others will argue a point to death when everyone else understands that
the point he's arguing was already agreed upon by everyone else. Instead of
arguing an actual point he is simply trying to make an argument around a
misunderstanding that sometimes is quite purposeful.

JG said:

Whoops, that should have been, "a one tenth of one percent change in a
meter of cable/housing translates into 4mm+ of slop"...

Jobst, why would you "take" something I haven't said? is it what you
want to hear? What I wrote was "cable/housing". Whether its housing
compression, or housing seating, or cable unkinking, or cable
stretching, the point is simply that it takes a rather small amount to
have a noticable effect because of the 4:1 multiplier.

of course. jobst is ust trying to fudge because he's messed up and his
ego prevents him from ever correcting that.

Quoted message said:

To tell the truth, I haven't paid much attention to what the two of
you are babbling about. It's just not as interesting as it was a
generation ago. I "take" cable stretch to usually mean non-elastic
elongation - and accept that it is a real result of a number of
factors not including meaningful physical elongation of the cable
itself, which are a product of industry bike setup practices. As for
the cable's contribution to the overall elasticity of the braking
system, it's all bs until someone pulls out the micrometer...

JG

Quoted message said:

someone said:

There's a lot of talk about measurements, but the dimensions are
pretty small. A one percent change in cable/housing translates into
4mm+ slop in a standard brake lever.

I take it you are trying to support the cable stretch adherents from
what you say. In contrast, I am proposing a simpler test, that of
noting whether there is any relative motion at the operating end of
the control cable.

why? the rider doesn't care about that - they care about whether the
lever bottoms against the handlebar because the system is too elastic!!!

Quoted message said:

Once the pads have made contact with the rim (I am
assume these are worn-in pads that make full contact), seeing whether
motion at the hand lever is producing movement at the exit of the
cable is a simple matter and one that resolves the stretch theory.

fudge.

Quoted message said:

Do it and you'll see that the cable is not stretching but in fact
transmitting force and motion.

deliberate avoidance.

it is a fundamental feature of stress that it be accompanied by strain.
with any system, it is simply ridiculous to focus on just one aspect,
then extrapolate that behavior to the whole.

JG said:

Quoted message said:

This is, however, a tech newsgroup and therefore there are some
expectations of accuracy and precision.- Hide quoted text -

To be precise and accurate, "some" means more than zero. There are
probably some expectations of accuracy and precision on
alt.garden.gnomes...

lol!!!!!

Tom Kunich said:

"JG" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Whoops, that should have been, "a one tenth of one percent change in a
meter of cable/housing translates into 4mm+ of slop"...

Jobst, why would you "take" something I haven't said? is it what you
want to hear? What I wrote was "cable/housing". Whether its housing
compression, or housing seating, or cable unkinking, or cable
stretching, the point is simply that it takes a rather small amount to
have a noticable effect because of the 4:1 multiplier.

Jobst is trying to be exact

actually, he's trying to bamboozle and [censored] because he's made yet
another fundamental mistake. clearly he's succeeding!

Quoted message said:

I suppose but that's what tends to irritate
normal people who assume that there are normal errors in descriptions.

Quoted message said:

I "take" cable stretch to usually mean non-elastic
elongation - and accept that it is a real result of a number of
factors not including meaningful physical elongation of the cable
itself, which are a product of industry bike setup practices. As for
the cable's contribution to the overall elasticity of the braking
system, it's all bs until someone pulls out the micrometer...

You and I have more or less the same take on it. Absolute precision in
writing and meaning isn't really part of the internet experience.

there's no reason there shouldn't be precision. just like there's no
reason to accept [censored].

"Tom Kunich" <cyclintom@yahoo. com> wrote in message
news:[email hidden]...

Quoted message said:

Sorry if you don't understand English Tim but the fact remains that most
people are quite satisfied with normal accuracy and precision. Jobst and a
few others will argue a point to death when everyone else understands that
the point he's arguing was already agreed upon by everyone else. Instead
of arguing an actual point he is simply trying to make an argument around
a misunderstanding that sometimes is quite purposeful.

By the way - I don't consider this to be all that bad. It's just
occasionally irritating. For the most part Jobst is a great resource for
this board and cycling in general.

In article <[email hidden]>,

Tom Kunich' cyclintom@yahoo. com said:

"Tim McNamara" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

In article
<[email hidden]>,

JG said:

> This is, however, a tech newsgroup and therefore there are some
> expectations of accuracy and precision.

To be precise and accurate, "some" means more than zero.

Indeed. Unfortunately in the context of my statement the degree of
accuracy and precision to be expected is not quantifiable. Nor was
that necessary for my intent, which simply to contradict Tom
Kunich's suggestion that accuracy and precision are alien to the
Internet or to Usenet. In this case your comment was directed more
to precision than accuracy.

Sorry if you don't understand English Tim but the fact remains that
most people are quite satisfied with normal accuracy and precision.

My reading comprehension remains good, Tom. Perhaps the problem is with
your writing abilities. What you wrote was:

Quoted message said:

Jobst is trying to be exact I suppose but that's what tends to irritate
normal people who assume that there are normal errors in descriptions.

and

Quoted message said:

Absolute precision in writing and meaning isn't really part of the
internet experience.

Now, this makes the error of being an overly broad statement.
*Absolute* precision in writing English is impossible. Adequate
precision- and more importantly, adequate accuracy- can be achieved with
some self-discipline and careful reasoning before writing. "Normal"
writing is generally inadequate for this in a tech newsgroup, although
since as a culture we do a lousy job of teaching effective reasoning
skills this should come as no surprise. Teaching formal logic should
begin in the 1st grade.

Quoted message said:

Jobst and a few others will argue a point to death when everyone else
understands that the point he's arguing was already agreed upon by
everyone else. Instead of arguing an actual point he is simply trying
to make an argument around a misunderstanding that sometimes is quite
purposeful.

Stop begging the question.

In article
<[email hidden]>,

JG said:

Quoted message said:

This is, however, a tech newsgroup and therefore there are some
expectations of accuracy and precision.- Hide quoted text -

To be precise and accurate, "some" means more than zero. There are
probably some expectations of accuracy and precision on
alt.garden.gnomes...

I expect the opposite. agg could never be a serious group.
Hyperbole, rancor, and vilification would be the order of the day.

--
Michael Press

Tom Kunich said:

Quoted message said:

I also considered using the shifter cable from an old Positron RD
to see if that would reduce the slack enough to get decent
performance out of the rear brake, as according to the yachting
world a solid wire is less springy than a multi strand wire(for a
given diameter).

Quoted message said:

The problem isn't the inner wire but the outer casing I believe.

As the following web site shows, this has been a bugaboo for a long
time, so much so that people designed cable housings to prevent this
kind of "cable stretch" in spite of it not occurring. The sponge in
brakes is elastic and most elastic elements are bending elements and
brake pads. Thecaliper is a bending element and the pads are
elastomers and have toe-in.

http://www.gravity-slaves.co.uk/main/?p=show_article&article_ID=127

Jobst Brandt

Tom Kunich said:

Quoted message said:

I also considered using the shifter cable from an old Positron RD
to see if that would reduce the slack enough to get decent
performance out of the rear brake, as according to the yachting
world a solid wire is less springy than a multi strand wire(for a
given diameter).

Quoted message said:

The problem isn't the inner wire but the outer casing I believe.

As the following web site shows, this has been a bugaboo for a long
time, so much so that people designed cable housings to prevent this
kind of "cable stretch", in spite of it not occurring. The sponge in
brakes is elastic, and the most elastic elements are bending elements
and brake pads. The caliper is a bending element and the pads are
elastomers and have toe-in.

http://www.gravity-slaves.co.uk/main/?p=show_article&article_ID=127

Jobst Brandt

Quoted message said:

Tom Kunich said:

Quoted message said:

I also considered using the shifter cable from an old Positron RD
to see if that would reduce the slack enough to get decent
performance out of the rear brake, as according to the yachting
world a solid wire is less springy than a multi strand wire(for a
given diameter).

Quoted message said:

The problem isn't the inner wire but the outer casing I believe.

As the following web site shows, this has been a bugaboo for a long
time, so much so that people designed cable housings to prevent this
kind of "cable stretch" in spite of it not occurring. The sponge in
brakes is elastic and most elastic elements are bending elements and
brake pads. Thecaliper is a bending element and the pads are
elastomers and have toe-in.

http://www.gravity-slaves.co.uk/main/?p=show_article&article_ID=127

oh, how the worm turns. only a few days ago, all brake elasticity was
attributable only to "elastomeric brake pads"!

10 points for audacity.
0 for consistency.

now, let's clear up this ridiculous inconsistency on "stretch". you use
that word interchangeably between the regimes of elasticity and
plasticity, flip-flopping depending on whichever suits your particular
argument as the thread unfurls.

coming from an "engineer" so fond of lecturing on the use of linguistic
precision, such sloppiness would normally be one of two things:

1. poor grasp of the concepts.
2. deliberate obfuscation to allow the great jobst brandt to bully
anyone who dare encroach on "his territory".

given the nature of proceedings so far however, we might actually be
observing both!

[email hidden said:

"].. The sponge in
brakes is elastic, and the most elastic elements are bending elements
and brake pads. The caliper is a bending element and the pads are
elastomers and have toe-in.
Jobst Brandt

But for the situation I encountered it doesn't matter which parts are compressing and which parts that are bending, as long as I only change one at a time. And by ONLY changing the brake wire I got better performance.
With wire A I couldn't get both rim clearance and wheel lock before lever bottoming out, but with wire B I could.
So either there was a difference in brake wire characteristics, or the other parts of the system managed a truly marvellous amount of bedding in from one ride to the next.

dabac said:

Quoted message said:

.. The sponge in
brakes is elastic, and the most elastic elements are bending elements
and brake pads. The caliper is a bending element and the pads are
elastomers and have toe-in.
Jobst Brandt

But for the situation I encountered it doesn't matter which parts are
compressing and which parts that are bending, as long as I only change
one at a time. And by ONLY changing the brake wire I got better
performance.
With wire A I couldn't get both rim clearance and wheel lock before
lever bottoming out, but with wire B I could.

that's probably just an adjustment thing. brake wire will not
plastically deform at anything near braking stresses.

the only other possibility is if some strands were broken, in which
case, the cable would appear to be more elastic, but you would have
noticed that.

Quoted message said:

So either there was a difference in brake wire characteristics,

brake wire is standard stuff - elasticities are essentially identical.

Quoted message said:

or the
other parts of the system managed a truly marvellous amount of bedding
in from one ride to the next.