# dual pivot brake caliper toe progression

J

#### jim beam

##### Guest
[email protected] wrote:
> On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
>
> What about a picture from the side? If the pads aren't parallel to
> the mounting bolt, this proves absolutely nothing.

It's difficult to tell from the photos, but it appears that there is an
eccentric motion to the pad on the right. As the brake closes, the
right pad not only moves towards the other pad but also forward (down,
in the photo). This could be explained by the pivots not being parallel
to each other.

[email protected] wrote:
> On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
>
> What about a picture from the side? If the pads aren't parallel to
> the mounting bolt, this proves absolutely nothing.

It's difficult to tell from the photos, but it appears that there is an
eccentric motion to the pad on the right. As the brake closes, the
right pad not only moves towards the other pad but also forward (down,
in the photo). This could be explained by the pivots not being parallel
to each other.

On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:
> [email protected] wrote:
> > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> >> for the skeptics.

>
>
>
>
> > What about a picture from the side? If the pads aren't parallel to
> > the mounting bolt, this proves absolutely nothing.

>
> It's difficult to tell from the photos, but it appears that there is an
> eccentric motion to the pad on the right. As the brake closes, the
> right pad not only moves towards the other pad but also forward (down,
> in the photo). This could be explained by the pivots not being parallel
> to each other.

look like all kinds of neat things are happening if you only took at
the brake from one direction. Square the pads up like they would be
on a bike (where some of us use our brakes) and the eccentricity goes
away. It's interesting that jim isn't even trying to show a front
brake doing the opposite.

On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:
> [email protected] wrote:
> > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> >> for the skeptics.

>
>
>
>
> > What about a picture from the side? If the pads aren't parallel to
> > the mounting bolt, this proves absolutely nothing.

>
> It's difficult to tell from the photos, but it appears that there is an
> eccentric motion to the pad on the right. As the brake closes, the
> right pad not only moves towards the other pad but also forward (down,
> in the photo). This could be explained by the pivots not being parallel
> to each other.

look like all kinds of neat things are happening if you only took at
the brake from one direction. Square the pads up like they would be
on a bike (where some of us use our brakes) and the eccentricity goes
away. It's interesting that jim isn't even trying to show a front
brake doing the opposite.

On Nov 9, 9:45 am, [email protected] wrote:
> On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:
>
>
>
> > [email protected] wrote:
> > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > >> for the skeptics.

>
>
>
>
> > > What about a picture from the side? If the pads aren't parallel to
> > > the mounting bolt, this proves absolutely nothing.

>
> > It's difficult to tell from the photos, but it appears that there is an
> > eccentric motion to the pad on the right. As the brake closes, the
> > right pad not only moves towards the other pad but also forward (down,
> > in the photo). This could be explained by the pivots not being parallel
> > to each other.

>
> look like all kinds of neat things are happening if you only took at
> the brake from one direction. Square the pads up like they would be
> on a bike (where some of us use our brakes) and the eccentricity goes
> away. It's interesting that jim isn't even trying to show a front
> brake doing the opposite.

Are you taking the position that jb is deliberately lying? IMO, he
believes his position is correct. I haven't taken the time to
'measure' both a front and rear Shimano or Campy set of dual pivots,
so I can't say yay or nay. But I do doubt he is willfully being

On Nov 9, 9:45 am, [email protected] wrote:
> On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:
>
>
>
> > [email protected] wrote:
> > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > >> for the skeptics.

>
>
>
>
> > > What about a picture from the side? If the pads aren't parallel to
> > > the mounting bolt, this proves absolutely nothing.

>
> > It's difficult to tell from the photos, but it appears that there is an
> > eccentric motion to the pad on the right. As the brake closes, the
> > right pad not only moves towards the other pad but also forward (down,
> > in the photo). This could be explained by the pivots not being parallel
> > to each other.

>
> look like all kinds of neat things are happening if you only took at
> the brake from one direction. Square the pads up like they would be
> on a bike (where some of us use our brakes) and the eccentricity goes
> away. It's interesting that jim isn't even trying to show a front
> brake doing the opposite.

Are you taking the position that jb is deliberately lying? IMO, he
believes his position is correct. I haven't taken the time to
'measure' both a front and rear Shimano or Campy set of dual pivots,
so I can't say yay or nay. But I do doubt he is willfully being

On Nov 9, 10:11 am, Ozark Bicycle
<[email protected]> wrote:
> On Nov 9, 9:45 am, [email protected] wrote:
>
>
>
> > On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:

>
> > > [email protected] wrote:
> > > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > > >> for the skeptics.

>
>
>
>
> > > > What about a picture from the side? If the pads aren't parallel to
> > > > the mounting bolt, this proves absolutely nothing.

>
> > > It's difficult to tell from the photos, but it appears that there is an
> > > eccentric motion to the pad on the right. As the brake closes, the
> > > right pad not only moves towards the other pad but also forward (down,
> > > in the photo). This could be explained by the pivots not being parallel
> > > to each other.

>
> > look like all kinds of neat things are happening if you only took at
> > the brake from one direction. Square the pads up like they would be
> > on a bike (where some of us use our brakes) and the eccentricity goes
> > away. It's interesting that jim isn't even trying to show a front
> > brake doing the opposite.

>
> Are you taking the position that jb is deliberately lying? IMO, he
> believes his position is correct. I haven't taken the time to
> 'measure' both a front and rear Shimano or Campy set of dual pivots,
> so I can't say yay or nay. But I do doubt he is willfully being

His level of animosity toward those who disagree with him is not
inconsistent with such behavior (willful lying to support incorrect
assertions).

D'ohBoy

On Nov 9, 10:11 am, Ozark Bicycle
<[email protected]> wrote:
> On Nov 9, 9:45 am, [email protected] wrote:
>
>
>
> > On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:

>
> > > [email protected] wrote:
> > > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > > >> for the skeptics.

>
>
>
>
> > > > What about a picture from the side? If the pads aren't parallel to
> > > > the mounting bolt, this proves absolutely nothing.

>
> > > It's difficult to tell from the photos, but it appears that there is an
> > > eccentric motion to the pad on the right. As the brake closes, the
> > > right pad not only moves towards the other pad but also forward (down,
> > > in the photo). This could be explained by the pivots not being parallel
> > > to each other.

>
> > look like all kinds of neat things are happening if you only took at
> > the brake from one direction. Square the pads up like they would be
> > on a bike (where some of us use our brakes) and the eccentricity goes
> > away. It's interesting that jim isn't even trying to show a front
> > brake doing the opposite.

>
> Are you taking the position that jb is deliberately lying? IMO, he
> believes his position is correct. I haven't taken the time to
> 'measure' both a front and rear Shimano or Campy set of dual pivots,
> so I can't say yay or nay. But I do doubt he is willfully being

His level of animosity toward those who disagree with him is not
inconsistent with such behavior (willful lying to support incorrect
assertions).

D'ohBoy

On Nov 9, 11:18 am, D'ohBoy <[email protected]> wrote:
> On Nov 9, 10:11 am, Ozark Bicycle
>
>
>
> <[email protected]> wrote:
> > On Nov 9, 9:45 am, [email protected] wrote:

>
> > > On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:

>
> > > > [email protected] wrote:
> > > > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > > > >> for the skeptics.

>
>
>
>
> > > > > What about a picture from the side? If the pads aren't parallel to
> > > > > the mounting bolt, this proves absolutely nothing.

>
> > > > It's difficult to tell from the photos, but it appears that there is an
> > > > eccentric motion to the pad on the right. As the brake closes, the
> > > > right pad not only moves towards the other pad but also forward (down,
> > > > in the photo). This could be explained by the pivots not being parallel
> > > > to each other.

>
> > > look like all kinds of neat things are happening if you only took at
> > > the brake from one direction. Square the pads up like they would be
> > > on a bike (where some of us use our brakes) and the eccentricity goes
> > > away. It's interesting that jim isn't even trying to show a front
> > > brake doing the opposite.

>
> > Are you taking the position that jb is deliberately lying? IMO, he
> > believes his position is correct. I haven't taken the time to
> > 'measure' both a front and rear Shimano or Campy set of dual pivots,
> > so I can't say yay or nay. But I do doubt he is willfully being

>
> His level of animosity toward those who disagree with him is not
> inconsistent with such behavior (willful lying to support incorrect
> assertions).
>

IMO, much of jb's animosity is a reaction to the animosity displayed
*toward* him. And that animosity springs from the fact that he has the
temerity to dispute the pronouncements of Jobst the Great and Mighty,
who has most people here cowed like a bunch of ****-eating sheep.

On Nov 9, 11:18 am, D'ohBoy <[email protected]> wrote:
> On Nov 9, 10:11 am, Ozark Bicycle
>
>
>
> <[email protected]> wrote:
> > On Nov 9, 9:45 am, [email protected] wrote:

>
> > > On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:

>
> > > > [email protected] wrote:
> > > > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > > > >> for the skeptics.

>
>
>
>
> > > > > What about a picture from the side? If the pads aren't parallel to
> > > > > the mounting bolt, this proves absolutely nothing.

>
> > > > It's difficult to tell from the photos, but it appears that there is an
> > > > eccentric motion to the pad on the right. As the brake closes, the
> > > > right pad not only moves towards the other pad but also forward (down,
> > > > in the photo). This could be explained by the pivots not being parallel
> > > > to each other.

>
> > > look like all kinds of neat things are happening if you only took at
> > > the brake from one direction. Square the pads up like they would be
> > > on a bike (where some of us use our brakes) and the eccentricity goes
> > > away. It's interesting that jim isn't even trying to show a front
> > > brake doing the opposite.

>
> > Are you taking the position that jb is deliberately lying? IMO, he
> > believes his position is correct. I haven't taken the time to
> > 'measure' both a front and rear Shimano or Campy set of dual pivots,
> > so I can't say yay or nay. But I do doubt he is willfully being

>
> His level of animosity toward those who disagree with him is not
> inconsistent with such behavior (willful lying to support incorrect
> assertions).
>

IMO, much of jb's animosity is a reaction to the animosity displayed
*toward* him. And that animosity springs from the fact that he has the
temerity to dispute the pronouncements of Jobst the Great and Mighty,
who has most people here cowed like a bunch of ****-eating sheep.

In article <[email protected]>,
Tim McNamara <[email protected]> wrote:
>It's difficult to tell from the photos, but it appears that there is an
>eccentric motion to the pad on the right. As the brake closes, the
>right pad not only moves towards the other pad but also forward (down,
>in the photo). This could be explained by the pivots not being parallel
>to each other.

It's not a matter of the pivots: the same thing happens with
single-pivot brakes with both brake arms pivoting on the same bolt.

This is a matter of the brake pads not being parallel to the
brake pivots. A rear brake has its pads mounted with their rear end
farther from the pivots than the front end. Being at a larger radius
from the pivot, the rear end moves more than the front. A front brake,
thanks to the offset off the fork, has its pads more parallel to its
pivot.

It's a stretch of the imagination to to think that this is a
deliberate effect though. More to the point of what started this
discussion, a front brake mounted on the rear has its pads at the same
angle relative to its pivots as a rear brake mounted on the rear.

-Luns

In article <[email protected]>,
Tim McNamara <[email protected]> wrote:
>It's difficult to tell from the photos, but it appears that there is an
>eccentric motion to the pad on the right. As the brake closes, the
>right pad not only moves towards the other pad but also forward (down,
>in the photo). This could be explained by the pivots not being parallel
>to each other.

It's not a matter of the pivots: the same thing happens with
single-pivot brakes with both brake arms pivoting on the same bolt.

This is a matter of the brake pads not being parallel to the
brake pivots. A rear brake has its pads mounted with their rear end
farther from the pivots than the front end. Being at a larger radius
from the pivot, the rear end moves more than the front. A front brake,
thanks to the offset off the fork, has its pads more parallel to its
pivot.

It's a stretch of the imagination to to think that this is a
deliberate effect though. More to the point of what started this
discussion, a front brake mounted on the rear has its pads at the same
angle relative to its pivots as a rear brake mounted on the rear.

-Luns

[email protected] wrote:

> On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:
>
>> [email protected] wrote:
>>
>>> On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
>>>
>>>> for the skeptics.
>>>>
>>>> http://www.flickr.com/photos/38636024@N00/1928128941/
>>>>
>>>> http://www.flickr.com/photos/38636024@N00/1928128939/
>>>>
>>>> http://www.flickr.com/photos/38636024@N00/1928128923/
>>>>
>>> What about a picture from the side? If the pads aren't parallel
>>> to the mounting bolt, this proves absolutely nothing.

>>
>> It's difficult to tell from the photos, but it appears that there
>> is an eccentric motion to the pad on the right. As the brake
>> closes, the right pad not only moves towards the other pad but also
>> forward (down, in the photo). This could be explained by the
>> pivots not being parallel to each other.

>
> look like all kinds of neat things are happening if you only took at
> the brake from one direction. Square the pads up like they would be
> on a bike (where some of us use our brakes) and the eccentricity
> goes away. It's interesting that jim isn't even trying to show a
> front brake doing the opposite.

Far be it from me to accept anything from "jim beam" at face value,
however I am not at all certain that the orientation of the pad would
produce the apparent effect shown in the photos. The apparent movement
is about 1/8". The sweep of the ends of the pads would be the same
regardless of their orientation.

The problem with the photo is that the brake is lying on an open book
rather than mounted firmly. If "jim beam" really wants to demonstrate
his point, he'd do better to mount the brake on a flat surface (e.g.,
drill a mounting hole through a board and mount the brake to it), which
would provide a plane reference surface against which to judge the
movement. I don't own a dual pivot brake or I'd do it myself.
Unfortunately, "jim beam" won't accept my suggestion simply because it
comes from me, so the point will remain moot.

If the eccentric motion is real, the likelier explanation is that the
pivot axes are not parallel.

(And what's up with Google Groups's removal of newlines from quoted
material? What a pain in the ass to have to keep fixing. That's 90%
of the legibility problem in these long threads. Google must fear the
whitespace. Jeez, I wish people would use real newsreaders.)

[email protected] wrote:

> On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:
>
>> [email protected] wrote:
>>
>>> On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
>>>
>>>> for the skeptics.
>>>>
>>>> http://www.flickr.com/photos/38636024@N00/1928128941/
>>>>
>>>> http://www.flickr.com/photos/38636024@N00/1928128939/
>>>>
>>>> http://www.flickr.com/photos/38636024@N00/1928128923/
>>>>
>>> What about a picture from the side? If the pads aren't parallel
>>> to the mounting bolt, this proves absolutely nothing.

>>
>> It's difficult to tell from the photos, but it appears that there
>> is an eccentric motion to the pad on the right. As the brake
>> closes, the right pad not only moves towards the other pad but also
>> forward (down, in the photo). This could be explained by the
>> pivots not being parallel to each other.

>
> look like all kinds of neat things are happening if you only took at
> the brake from one direction. Square the pads up like they would be
> on a bike (where some of us use our brakes) and the eccentricity
> goes away. It's interesting that jim isn't even trying to show a
> front brake doing the opposite.

Far be it from me to accept anything from "jim beam" at face value,
however I am not at all certain that the orientation of the pad would
produce the apparent effect shown in the photos. The apparent movement
is about 1/8". The sweep of the ends of the pads would be the same
regardless of their orientation.

The problem with the photo is that the brake is lying on an open book
rather than mounted firmly. If "jim beam" really wants to demonstrate
his point, he'd do better to mount the brake on a flat surface (e.g.,
drill a mounting hole through a board and mount the brake to it), which
would provide a plane reference surface against which to judge the
movement. I don't own a dual pivot brake or I'd do it myself.
Unfortunately, "jim beam" won't accept my suggestion simply because it
comes from me, so the point will remain moot.

If the eccentric motion is real, the likelier explanation is that the
pivot axes are not parallel.

(And what's up with Google Groups's removal of newlines from quoted
material? What a pain in the ass to have to keep fixing. That's 90%
of the legibility problem in these long threads. Google must fear the
whitespace. Jeez, I wish people would use real newsreaders.)

On Nov 9, 11:33 am, Ozark Bicycle
<[email protected]> wrote:
> On Nov 9, 11:18 am, D'ohBoy <[email protected]> wrote:
>
>
>
> > On Nov 9, 10:11 am, Ozark Bicycle

>
> > <[email protected]> wrote:
> > > On Nov 9, 9:45 am, [email protected] wrote:

>
> > > > On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:

>
> > > > > [email protected] wrote:
> > > > > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > > > > >> for the skeptics.

>
>
>
>
> > > > > > What about a picture from the side? If the pads aren't parallel to
> > > > > > the mounting bolt, this proves absolutely nothing.

>
> > > > > It's difficult to tell from the photos, but it appears that there is an
> > > > > eccentric motion to the pad on the right. As the brake closes, the
> > > > > right pad not only moves towards the other pad but also forward (down,
> > > > > in the photo). This could be explained by the pivots not being parallel
> > > > > to each other.

>
> > > > look like all kinds of neat things are happening if you only took at
> > > > the brake from one direction. Square the pads up like they would be
> > > > on a bike (where some of us use our brakes) and the eccentricity goes
> > > > away. It's interesting that jim isn't even trying to show a front
> > > > brake doing the opposite.

>
> > > Are you taking the position that jb is deliberately lying? IMO, he
> > > believes his position is correct. I haven't taken the time to
> > > 'measure' both a front and rear Shimano or Campy set of dual pivots,
> > > so I can't say yay or nay. But I do doubt he is willfully being

>
> > His level of animosity toward those who disagree with him is not
> > inconsistent with such behavior (willful lying to support incorrect
> > assertions).

>
> IMO, much of jb's animosity is a reaction to the animosity displayed
> *toward* him. And that animosity springs from the fact that he has the
> temerity to dispute the pronouncements of Jobst the Great and Mighty,
> who has most people here cowed like a bunch of ****-eating sheep.

I am neither in nor out of either camp. And I didn't say he *DID*
lie. And don't look now, but your bias is showing.

D'ohBoy

On Nov 9, 11:33 am, Ozark Bicycle
<[email protected]> wrote:
> On Nov 9, 11:18 am, D'ohBoy <[email protected]> wrote:
>
>
>
> > On Nov 9, 10:11 am, Ozark Bicycle

>
> > <[email protected]> wrote:
> > > On Nov 9, 9:45 am, [email protected] wrote:

>
> > > > On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:

>
> > > > > [email protected] wrote:
> > > > > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > > > > >> for the skeptics.

>
>
>
>
> > > > > > What about a picture from the side? If the pads aren't parallel to
> > > > > > the mounting bolt, this proves absolutely nothing.

>
> > > > > It's difficult to tell from the photos, but it appears that there is an
> > > > > eccentric motion to the pad on the right. As the brake closes, the
> > > > > right pad not only moves towards the other pad but also forward (down,
> > > > > in the photo). This could be explained by the pivots not being parallel
> > > > > to each other.

>
> > > > look like all kinds of neat things are happening if you only took at
> > > > the brake from one direction. Square the pads up like they would be
> > > > on a bike (where some of us use our brakes) and the eccentricity goes
> > > > away. It's interesting that jim isn't even trying to show a front
> > > > brake doing the opposite.

>
> > > Are you taking the position that jb is deliberately lying? IMO, he
> > > believes his position is correct. I haven't taken the time to
> > > 'measure' both a front and rear Shimano or Campy set of dual pivots,
> > > so I can't say yay or nay. But I do doubt he is willfully being

>
> > His level of animosity toward those who disagree with him is not
> > inconsistent with such behavior (willful lying to support incorrect
> > assertions).

>
> IMO, much of jb's animosity is a reaction to the animosity displayed
> *toward* him. And that animosity springs from the fact that he has the
> temerity to dispute the pronouncements of Jobst the Great and Mighty,
> who has most people here cowed like a bunch of ****-eating sheep.

I am neither in nor out of either camp. And I didn't say he *DID*
lie. And don't look now, but your bias is showing.

D'ohBoy

On Nov 9, 1:08 pm, D'ohBoy <[email protected]> wrote:
> On Nov 9, 11:33 am, Ozark Bicycle
>
>
>
> <[email protected]> wrote:
> > On Nov 9, 11:18 am, D'ohBoy <[email protected]> wrote:

>
> > > On Nov 9, 10:11 am, Ozark Bicycle

>
> > > <[email protected]> wrote:
> > > > On Nov 9, 9:45 am, [email protected] wrote:

>
> > > > > On Nov 9, 10:22 am, Tim McNamara <[email protected]> wrote:

>
> > > > > > [email protected] wrote:
> > > > > > > On Nov 9, 12:47 am, jim beam <[email protected]> wrote:
> > > > > > >> for the skeptics.

>
> > > > > > >>http://www.flickr.com/photos/38636024@N00/1928128941/

>
> > > > > > >>http://www.flickr.com/photos/38636024@N00/1928128939/

>
> > > > > > >>http://www.flickr.com/photos/38636024@N00/1928128923/

>
> > > > > > > What about a picture from the side? If the pads aren't parallel to
> > > > > > > the mounting bolt, this proves absolutely nothing.

>
> > > > > > It's difficult to tell from the photos, but it appears that there is an
> > > > > > eccentric motion to the pad on the right. As the brake closes, the
> > > > > > right pad not only moves towards the other pad but also forward (down,
> > > > > > in the photo). This could be explained by the pivots not being parallel
> > > > > > to each other.

>
> > > > > That's the great thing about orbital pad adjustment. You can make it
> > > > > look like all kinds of neat things are happening if you only took at
> > > > > the brake from one direction. Square the pads up like they would be
> > > > > on a bike (where some of us use our brakes) and the eccentricity goes
> > > > > away. It's interesting that jim isn't even trying to show a front
> > > > > brake doing the opposite.

>
> > > > Are you taking the position that jb is deliberately lying? IMO, he
> > > > believes his position is correct. I haven't taken the time to
> > > > 'measure' both a front and rear Shimano or Campy set of dual pivots,
> > > > so I can't say yay or nay. But I do doubt he is willfully being

>
> > > His level of animosity toward those who disagree with him is not
> > > inconsistent with such behavior (willful lying to support incorrect
> > > assertions).

>
> > IMO, much of jb's animosity is a reaction to the animosity displayed
> > *toward* him. And that animosity springs from the fact that he has the
> > temerity to dispute the pronouncements of Jobst the Great and Mighty,
> > who has most people here cowed like a bunch of ****-eating sheep.

>
> I am neither in nor out of either camp.

Did I imply you were?

> And I didn't say he *DID*
> lie.

Not explicitly, no.

And don't look now, but your bias is showing.
>

A bias of having had more than a full dose of Jobst the Great and
Mighty? You bet!!

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