brake failure

Quoted message said:

Quoted message said:

Quoted message said:

> We aren't getting any closer to the answer of MA or linearity.

Quoted message said:

Quoted message said:

Clive George said:

Not helped by you deliberately ignoring what's going on. The cable
pull for a V/linear brake system is more than for others, thus the
MA of the brake end is different. However this is compensated for
in the lever, thus the MA for the total system returns to being the
same.

Quoted message said:

<[email hidden]> wrote

Quoted message said:

That is what I was trying to resolve. The way it was first stated,
one would believe that the overall mechanical advantage was greater
than with other brakes, therefore greater stopping force, something
that is not reasonably possible, so thanks for "the same" statement.

Quoted message said:

Quoted message said:

Clive George said:

There are _two_ different MAs to consider - the one you're going on
about, for the whole system, is useful for some things, and the one
everybody else is going on about, that of cable travel to pad
travel, is useful for people who wish to know how to make components
work together.

Quoted message said:

<[email hidden]> wrote

Quoted message said:

To me it was a method by which the V-brake caliper could be made to
work without running out of hand reach. Meanwhile much hay has been
made of its supposed greater MA and linearity for better performance.

Clive George said:

Ah, that's a different problem :-)

AIUI one reason they're better than conventional cantis because the MA
is closer to linear - doesn't the geometry of conventional cantis work
against them in that regard? OTOH they also had thinner pads, which
gives an improvement at the expense of durability.
But I mustn't forget the pads - I hate conventional canti pads, cos
they're too darn hard to set up :-)

On a tandem, Vs should be better for the back, because the cable stretch
would be less of an issue with the travel being doubled and hence the
force halved.

"cable stretch"
?
Oh, now you've done it. Long thread coming...
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

Clive George said:

Quoted message said:

Quoted message said:

> We aren't getting any closer to the answer of MA or linearity.

Quoted message said:

Quoted message said:

Quoted message said:

Not helped by you deliberately ignoring what's going on. The
cable pull for a V/linear brake system is more than for others,
thus the MA of the brake end is different. However this is
compensated for in the lever, thus the MA for the total system
returns to being the same.

Quoted message said:

Quoted message said:

That is what I was trying to resolve. The way it was first stated,
one would believe that the overall mechanical advantage was greater
than with other brakes, therefore greater stopping force, something
that is not reasonably possible, so thanks for "the same"
statement.

Quoted message said:

Quoted message said:

Quoted message said:

There are _two_ different MAs to consider - the one you're going
on about, for the whole system, is useful for some things, and the
one everybody else is going on about, that of cable travel to pad
travel, is useful for people who wish to know how to make
components work together.

Quoted message said:

Quoted message said:

To me it was a method by which the V-brake caliper could be made to
work without running out of hand reach. Meanwhile much hay has
been made of its supposed greater MA and linearity for better
performance.

Quoted message said:

Ah, that's a different problem :-)

Quoted message said:

AIUI one reason they're better than conventional cantis because the
MA is closer to linear - doesn't the geometry of conventional cantis
work against them in that regard? OTOH they also had thinner pads,
which gives an improvement at the expense of durability. But I
mustn't forget the pads - I hate conventional canti pads, cos
they're too darn hard to set up :-)

Quoted message said:

On a tandem, Vs should be better for the back, because the cable
stretch would be less of an issue with the travel being doubled and
hence the force halved.

Consider the design problem. The V-brake got rid of the straddle
cable and brake lever elbows that stuck out making a simpler and
slimmer mechanism. To achieve good tire clearance, brake levers
extended far above the pads making an undesirable mechanical advantage
that had to be corrected with appropriate hand levers.

The first thing that followed in response to user complaints was the
"travel agent" to give compatibility for folks who didn't want to
throw out their accustomed hand levers. In any event, the MA is not
significantly different and pad sweep still leads to drop under as
cantilevers did.

I asked what the MA and linearity was because I don't believe either
of these is different from cantilevers they replace. It is a simpler
design and does not have the hazard of dropping a straddle cable onto
a knobby tire, an effect that causes an immediate endo. To make up
for that, their long thin pads wear out faster and have no benefit
other than being different from other brakes.

Jobst Brandt

Quoted message said:

clare who? said:

Quoted message said:

> I asked what the effective MA of the brake is from hand lever to
> brake pad and what brake pad and what made it "linear".

OK, how much more linear and how about a graph of had lever motion vs
pad motion comparing the most common brakes.

Quoted message said:

What makes it linear?

Quoted message said:

The mechanical advantage does not change with either the position of
the brake handle, or the position of the pad. Moving the handle the
first 1/16" moves the pads the same distance as the last 1/16"
(within a VERY small variance - so small as to be inconsequential)
This is NOT true of a center-pull or a cantilever because the angle
of the pull changes in an "arc" both at the handle end and at the
"caliper" end. Worse yet, the non-linearity ADDS instead of
canceling. The dual pivot "linear pull" handles pull straight - as
does the "V" brake "caliper".

Show how much this is on a graph.

You are the scientist, and you want the proof, YOU make the graph.

Quoted message said:

Quoted message said:

Really quite a simple concept.

Not simple at all. Just recall how long it took the concept of the
Dual Pivot brake to be even partly understood and why two pivots.

We aren't getting any closer to the answer of MA or linearity.

Jobst Brandt

Because you ain't listening??

** Posted from http://www.teranews.com **

Quoted message said:

Clive George said:

Quoted message said:

We aren't getting any closer to the answer of MA or linearity.

Quoted message said:

Not helped by you deliberately ignoring what's going on. The cable
pull for a V/linear brake system is more than for others, thus the
MA of the brake end is different. However this is compensated for
in the lever, thus the MA for the total system returns to being the
same.

That is what I was trying to resolve. The way it was first stated,
one would believe that the overall mechanical advantage was greater
than with other brakes, therefore greater stopping force, something
that is not reasonably possible, so thanks for "the same" statement.

Quoted message said:

There are _two_ different MAs to consider - the one you're going on
about, for the whole system, is useful for some things, and the one
everybody else is going on about, that of cable travel to pad
travel, is useful for people who wish to know how to make components
work together.

To me it was a method by which the V-brake caliper could be made to
work without running out of hand reach. Meanwhile much hay has been
made of its supposed greater MA and linearity for better performance.

Jobst Brandt

The maximum MA is not likely any better with the "V" brake, but it is
consistent -linear - and therefore gives a better brake feel and in my
experience slightly better brake "action".
** Posted from http://www.teranews.com **

There are several reasons why "linear" brakes now own the market.
Considerably easier setup, slightly better overall leverage ratios
leading to a lighter feel, useful for mountain bikes. (Lighter feel is
also the primary reason for increasing disc sizes on mountain bikes.)
And the leverage ratio is almost completely unchanged throughout the
lever stroke, which is something maddening about cantilever brakes as
can easily be ascertained with Sheldon's discussion of straddle cable
setup. As a downside to the higher overall leverage ratio, pads do
have to be set closer to the rim. This does have one beneficial effect
of reducing pad dive under the rim.

Large amounts of braking force are lost in the cable and housing
system. Thus doubling of cable travel halves this lost force, also
increasing braking efficiency and contributing to the rapid conversion
to "linear" pull brakes over cantilevers. This is the same effect used
by SRAM in their "1:1" rear derailleur shifting system to halve the
effect of friction on shifting precision. Lost force reduction also
accounts for the popularity of hydraulic disc brakes versus cable
activated disc brakes despite their complexity.

someone said:

There are several reasons why "linear" brakes now own the market.
Considerably easier setup, slightly better overall leverage ratios
leading to a lighter feel, useful for mountain bikes. (Lighter feel
is also the primary reason for increasing disc sizes on mountain
bikes.) And the leverage ratio is almost completely unchanged
throughout the lever stroke, which is something maddening about
cantilever brakes as can easily be ascertained with Sheldon's
discussion of straddle cable setup. As a downside to the higher
overall leverage ratio, pads do have to be set closer to the rim.
This does have one beneficial effect of reducing pad dive under the
rim.

I don't see any evidence for these claims that echo promotional copy.
As was mentioned, these do not have a significantly different MA.
Sheldon's article has no measurements or meaningful force diagrams to
support "common knowledge".

Quoted message said:

Large amounts of braking force are lost in the cable and housing
system. Thus doubling of cable travel halves this lost force, also
increasing braking efficiency and contributing to the rapid
conversion to "linear" pull brakes over cantilevers. This is the
same effect used by SRAM in their "1:1" rear derailleur shifting
system to halve the effect of friction on shifting precision. Lost
force reduction also accounts for the popularity of hydraulic disc
brakes versus cable activated disc brakes despite their complexity.

Hold the phone... we've been here before. Empty claims and religion!
This is so much deja-vu from the days of the centerpull heyday where
all these claims were also made... or better yet, alluded to and the
faithful followed the leader and solidified the beliefs.

Jobst Brandt

I'm having trouble figuring out what is being argued, er discussed, in
this thread...

1. 'Linear' is a perfectly obvious concept and one I've seen Jobst
embrace in previous posts. The horizontal displacement of the brakes
pads of a V brake move in fixed proportion (MA of the calipers) to the
horizontal displacement of the cable anchor points.

2. All brakes are probably close to linear in the distance between pad
contact and pad deforming, caliper bending, fork twisting full
application. However, figuring out what that is, is complicated by
yoke configuration.

3. High profile cantilevers, set near horizontal (i.e. MAFAC's) are
not only linear in the above sense, but of fixed MA as they are
indifferent to changes in yoke length.

4. Cantilevers don't dive down much more than center pivoted brakes in
their immediate ranges. This is easily determined by running a string
from the fork center to a cantilever mount and observing it passes
pretty close to the rim. (Dual pivots have some advantage here.)

5. All brake systems (okay not hydraulics) change their geometry with
pad wear. There is no need for V brakes to have thin pads. The
correct solution is to maintain the pad surface in the same plane -
hence the shaft mount of traditional cantilevers.

JG

someone said:

I'm having trouble figuring out what is being argued, er discussed,
in this thread...

Quoted message said:

1. 'Linear' is a perfectly obvious concept and one I've seen Jobst
embrace in previous posts. The horizontal displacement of the
brakes pads of a V brake move in fixed proportion (MA of the
calipers) to the horizontal displacement of the cable anchor points.

Quoted message said:

2. All brakes are probably close to linear in the distance between
pad contact and pad deforming, caliper bending, fork twisting full
application. However, figuring out what that is, is complicated by
yoke configuration.

Quoted message said:

3. High profile cantilevers, set near horizontal (i.e. MAFAC's) are
not only linear in the above sense, but of fixed MA as they are
indifferent to changes in yoke length.

Quoted message said:

4. Cantilevers don't dive down much more than center pivoted brakes
in their immediate ranges. This is easily determined by running a
string from the fork center to a cantilever mount and observing it
passes pretty close to the rim. (Dual pivots have some advantage
here.)

Dive is given by the position of the pivot around which the brake arm
rotates. In the sidepull single pivot, the pivot is centered over the
rim and has essentially zero cosine error (foreshortening as it
articulates). The cantilever has large cosine error, arcing at close
to 45 degrees from the contact area. V-brakes, using the same pivot
points do likewise.

Quoted message said:

5. All brake systems (okay not hydraulics) change their geometry
with pad wear. There is no need for V brakes to have thin pads.
The correct solution is to maintain the pad surface in the same
plane - hence the shaft mount of traditional cantilevers.

Not true. With classic sidepull brakes, pads can be worn to the metal
(pad holder) without changing enough to require adjustment. I do it
all the time with my brakes.

I take it trigonometry is no longer taught in schools.

Jobst Brandt

Quoted message said:

someone said:

There are several reasons why "linear" brakes now own the market.
Considerably easier setup, slightly better overall leverage ratios
leading to a lighter feel, useful for mountain bikes. (Lighter feel
is also the primary reason for increasing disc sizes on mountain
bikes.) And the leverage ratio is almost completely unchanged
throughout the lever stroke, which is something maddening about
cantilever brakes as can easily be ascertained with Sheldon's
discussion of straddle cable setup. As a downside to the higher
overall leverage ratio, pads do have to be set closer to the rim.
This does have one beneficial effect of reducing pad dive under the
rim.

I don't see any evidence for these claims that echo promotional copy.
As was mentioned, these do not have a significantly different MA.
Sheldon's article has no measurements or meaningful force diagrams to
support "common knowledge".

Quoted message said:

Large amounts of braking force are lost in the cable and housing
system. Thus doubling of cable travel halves this lost force, also
increasing braking efficiency and contributing to the rapid
conversion to "linear" pull brakes over cantilevers. This is the
same effect used by SRAM in their "1:1" rear derailleur shifting
system to halve the effect of friction on shifting precision. Lost
force reduction also accounts for the popularity of hydraulic disc
brakes versus cable activated disc brakes despite their complexity.

Hold the phone... we've been here before. Empty claims and religion!
This is so much deja-vu from the days of the centerpull heyday where
all these claims were also made... or better yet, alluded to and the
faithful followed the leader and solidified the beliefs.

Jobst Brandt

Lets stop feeding the (deaf) troll.
** Posted from http://www.teranews.com **

In article <[email hidden]>,

Quoted message said:

I take it trigonometry is no longer taught in schools.

Depends. Is it on the tests required by NCLB? If it ain't on the
tests, it ain't in the classroom.

Tim McNamara said:

Quoted message said:

I take it trigonometry is no longer taught in schools.

Quoted message said:

Depends. Is it on the tests required by NCLB? If it ain't on the
tests, it ain't in the classroom.

I should have said that it isn't shown where angle functions enter
into our daily lives. I have yet to meet a recent engineer who knows
what cosine error is. They have a hard enough time keeping sine and
cosine apart. These same folks ride bike and claim to understand
things like rim and disk brakes and don't see the difference between
arguing and discussing the merits of one design over another.

Jobst Brandt

Quoted message said:

Tim McNamara said:

Quoted message said:

I take it trigonometry is no longer taught in schools.

Quoted message said:

Depends. Is it on the tests required by NCLB? If it ain't on the
tests, it ain't in the classroom.

I should have said that it isn't shown where angle functions enter
into our daily lives. I have yet to meet a recent engineer who knows
what cosine error is. They have a hard enough time keeping sine and
cosine apart.

quoth the "engineer" that can't recognize how straddle cable angle
affects mechanical advantage.

Quoted message said:

These same folks ride bike and claim to understand
things like rim and disk brakes and don't see the difference between
arguing and discussing the merits of one design over another.

quoth the "engineer" that can't recognize how straddle cable angle
affects mechanical advantage.

you're quite amazing jobst. your inability to read or learn is somehow
completely juxtaposed to your phenomenal ability to attribute your own
faults to others. it really is absolutely incredible.

Tom Kunich said:

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

Quoted message said:

Quoted message said:

For that reason, measuring
hand lever stroke and combined pad(s) stroke is the only unambiguous
measure of MA. The article by Sheldon is as vague as claims by brake
manufacturers.

rubbish jobst. the math is clear and unambiguous.

Jim, because of your dislike of Jobst's style you're failing to
understand what he's saying. In truth he is correct that in order to get
the same BRAKE PAD TRAVEL you need to have the same overall ratios.
There is a small problem in that idea though - in order to make the
brake lever forces smaller, they set the system up to use SHORTER
TRAVEL. The results of this is that linear brakes have to have very
straight wheels and the pads are set much closer to the rims.

there's two things - the leverage ratios you refer to for "v" and
caliper brakes, and the leverage ratios for cantilevers. the latter is
variable, as a function of straddle cable angle.

Quoted message said:

So in truth the linear braking system does use a higher MA but at the
cost of higher maintenance.

higher maintenance???

Quoted message said:

someone said:

There are several reasons why "linear" brakes now own the market.
Considerably easier setup, slightly better overall leverage ratios
leading to a lighter feel, useful for mountain bikes. (Lighter feel
is also the primary reason for increasing disc sizes on mountain
bikes.) And the leverage ratio is almost completely unchanged
throughout the lever stroke, which is something maddening about
cantilever brakes as can easily be ascertained with Sheldon's
discussion of straddle cable setup. As a downside to the higher
overall leverage ratio, pads do have to be set closer to the rim.
This does have one beneficial effect of reducing pad dive under the
rim.

I don't see any evidence for these claims that echo promotional copy.
As was mentioned, these do not have a significantly different MA.
Sheldon's article has no measurements or meaningful force diagrams to
support "common knowledge".

eh? like your presentation of a wheel load calculation and using it to
"demonstrate" how wheel strength, er, "increases" with spoke tension?

Quoted message said:

Quoted message said:

Large amounts of braking force are lost in the cable and housing
system. Thus doubling of cable travel halves this lost force, also
increasing braking efficiency and contributing to the rapid
conversion to "linear" pull brakes over cantilevers. This is the
same effect used by SRAM in their "1:1" rear derailleur shifting
system to halve the effect of friction on shifting precision. Lost
force reduction also accounts for the popularity of hydraulic disc
brakes versus cable activated disc brakes despite their complexity.

Hold the phone... we've been here before. Empty claims and religion!
This is so much deja-vu from the days of the centerpull heyday where
all these claims were also made... or better yet, alluded to and the
faithful followed the leader and solidified the beliefs.

jobst, the math is very clear*. the only person around here that
doesn't seem to get it is you. allusions to "Empty claims and
religion!" result from the specters of your own disordered mind.

* it's notable how you don't use any in your, er, "argument" on this
subject.

In article
<[email hidden]>,

velodancer said:

There are several reasons why "linear" brakes now own the market.
Considerably easier setup, slightly better overall leverage ratios
leading to a lighter feel, useful for mountain bikes. (Lighter feel is
also the primary reason for increasing disc sizes on mountain bikes.)
And the leverage ratio is almost completely unchanged throughout the
lever stroke, which is something maddening about cantilever brakes as
can easily be ascertained with Sheldon's discussion of straddle cable
setup. As a downside to the higher overall leverage ratio, pads do
have to be set closer to the rim. This does have one beneficial effect
of reducing pad dive under the rim.

Large amounts of braking force are lost in the cable and housing
system. Thus doubling of cable travel halves this lost force, also
increasing braking efficiency and contributing to the rapid conversion
to "linear" pull brakes over cantilevers. This is the same effect used
by SRAM in their "1:1" rear derailleur shifting system to halve the
effect of friction on shifting precision. Lost force reduction also
accounts for the popularity of hydraulic disc brakes versus cable
activated disc brakes despite their complexity.

There a many solutions to replace single pivot calipers,
but none of them measure up. Adding up advantages and
disadvantages, single pivot calipers are the best. When
you need to improve some aspect of brake performance
over single pivot calipers, then you must compromise
others. Typically one of the advantages we abandon when
we abandon single pivot calipers is the minimal maintenance.
Nobody here writes in with questions on setting up and
maintaining single pivot calipers. (of course they are
not produce any more except BMX 75-90 mm reach.)

For me there are three improvements in brakes in the
last fifty years: lined cable housing, aerodynamic
brake levers, and orange brake pads. The rest is
optimization of exactly one component of brake performance.

--
Michael Press

In article <[email hidden]>,

Quoted message said:

someone said:

I'm having trouble figuring out what is being argued, er discussed,
in this thread...

Quoted message said:

1. 'Linear' is a perfectly obvious concept and one I've seen Jobst
embrace in previous posts. The horizontal displacement of the
brakes pads of a V brake move in fixed proportion (MA of the
calipers) to the horizontal displacement of the cable anchor points.

Quoted message said:

2. All brakes are probably close to linear in the distance between
pad contact and pad deforming, caliper bending, fork twisting full
application. However, figuring out what that is, is complicated by
yoke configuration.

Quoted message said:

3. High profile cantilevers, set near horizontal (i.e. MAFAC's) are
not only linear in the above sense, but of fixed MA as they are
indifferent to changes in yoke length.

Quoted message said:

4. Cantilevers don't dive down much more than center pivoted brakes
in their immediate ranges. This is easily determined by running a
string from the fork center to a cantilever mount and observing it
passes pretty close to the rim. (Dual pivots have some advantage
here.)

Dive is given by the position of the pivot around which the brake arm
rotates. In the sidepull single pivot, the pivot is centered over the
rim and has essentially zero cosine error (foreshortening as it
articulates). The cantilever has large cosine error, arcing at close
to 45 degrees from the contact area. V-brakes, using the same pivot
points do likewise.

Quoted message said:

5. All brake systems (okay not hydraulics) change their geometry
with pad wear. There is no need for V brakes to have thin pads.
The correct solution is to maintain the pad surface in the same
plane - hence the shaft mount of traditional cantilevers.

Not true. With classic sidepull brakes, pads can be worn to the metal
(pad holder) without changing enough to require adjustment. I do it
all the time with my brakes.

I take it trigonometry is no longer taught in schools.

I do not know how well it was ever taught. We had a physics
teacher who one day said "Today I teach you trigonometry",
and he did. Of course he had our attention 'cause he used
to tell us war stories, and about what it was like for a
17 year old to steep in a south Pacific foxhole all night
while Japanese soldiers screamed at you and promised to
inflict abominations upon your flesh. The rest of the
hour after he taught us trigonometry he told war stories.

Trigonometry only gets a bit complicated/interesting
when you would like to figure the angles on a complex mitre
for carpentry, or two twisted eighth bends while plumbing,
or the geodesic distance given latitude and longitude
of two points.

--
Michael Press

[email hidden] wrote in news:48347bea$0$34514
[email hidden]:

Quoted message said:

To make up for that, their long thin pads wear out faster and have no
benefit other than being different from other brakes.

Jobst Brandt

V brake pads are much easier to install and align than any canti brake I
had before.

--
Larry Dickman <[email hidden]>

Michael Press said:

Quoted message said:

There are several reasons why "linear" brakes now own the market.
Considerably easier setup, slightly better overall leverage ratios
leading to a lighter feel, useful for mountain bikes. (Lighter
feel is also the primary reason for increasing disc sizes on
mountain bikes.) And the leverage ratio is almost completely
unchanged throughout the lever stroke, which is something maddening
about cantilever brakes as can easily be ascertained with Sheldon's
discussion of straddle cable setup. As a downside to the higher
overall leverage ratio, pads do have to be set closer to the rim.
This does have one beneficial effect of reducing pad dive under the
rim.

Quoted message said:

Quoted message said:

Large amounts of braking force are lost in the cable and housing
system. Thus doubling of cable travel halves this lost force, also
increasing braking efficiency and contributing to the rapid
conversion to "linear" pull brakes over cantilevers. This is the
same effect used by SRAM in their "1:1" rear derailleur shifting
system to halve the effect of friction on shifting precision. Lost
force reduction also accounts for the popularity of hydraulic disc
brakes versus cable activated disc brakes despite their complexity.

Quoted message said:

There a many solutions to replace single pivot calipers, but none of
them measure up. Adding up advantages and disadvantages, single
pivot calipers are the best. When you need to improve some aspect
of brake performance over single pivot calipers, then you must
compromise others. Typically one of the advantages we abandon when
we abandon single pivot calipers is the minimal maintenance. Nobody
here writes in with questions on setting up and maintaining single
pivot calipers. (of course they are not produce any more except BMX
75-90 mm reach.)

Quoted message said:

For me there are three improvements in brakes in the last fifty
years: lined cable housing, aerodynamic brake levers, and orange
brake pads. The rest is optimization of exactly one component of
brake performance.

A problem with single pivot brakes is that the caliper return spring
has significant cosine error causing spring sliding at contact points
on its brake arms. The spring rotation centers are in the two ram's
horn coils on either side of the brake anchor. With a return spring
having a single coil wrapped around the anchor about which brake arms
rotate has no cosine error. This makes a reliable self centering
caliper that does not need "dual pivot" remain centered and prevent
one sided brake drag.

On conventional single pivot brake calipers, drag can only be avoided
keeping spring contact points clean and lubricated. I am amazed that
brake designers missed that point. This is apparent on the dual pivot
brake because it has greater cosine error than prior single pivot
brakes and uses a special plastic slider bearing to accommodate that
greater spring-to-brake-arm motion.

Are we making any progress yet?

Jobst Brandt

No, the angle a centerpull makes to the rim is roughly the same as a
cantilever does... However, the radius of the centerpull is about
twice as long, so it will dive twice as much as the neglible
centerpull dive. Of course, I cheated and actually looked at a
bike...

One reason for thin V brake pads is that while thick pads are
perfectly viable, a 2.5 MA would mean the arms would have to be
adjusted through 2.5 x 2 pad thicknesses, which would be rather
inelegant...

JG

Larry Dickman said:

Quoted message said:

To make up for that, their long thin pads wear out faster and have
no benefit other than being different from other brakes.

Quoted message said:

V brake pads are much easier to install and align than any canti
brake I had before.

Why? I don't see what their length and thinness has to do with
installation. My Kool-Stop Continental pads are as simple as can be
and they last a long time.

Jobst Brandt