Re: Brake Reach Measurement ?

Sheldon Brown said:

I've got a couple of pretty decent photos in my Bicycle Glossary at:

I got a 404 on this, did anyone else?

--
Andy Morris

AndyAtJinkasDotFreeserve.Co.UK

Love this:
Put an end to Outlook Express's messy quotes
http://home.in.tum.de/~jain/software/oe-quotefix/

I said:

Quoted message said:

I've got a couple of pretty decent photos in my Bicycle Glossary at:

http://sheldonbrown.com/reach

Andy Morris said:

I got a 404 on this, did anyone else?

Sorry, I had forgotten to upload the shortcut.

It's working now.

Sheldon "Oops!" Brown
+-------------------------------------------+
| Genius may have its limitations, |
| but stupidity is not thus handicapped. |
| --Elbert Hubbard |
+-------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

dig it!!
i put'um on seat stay backwards to get the cable thru the 1 ton rear
rack mount then wondered (for years) why the arms were tooooo short.

Sheldon Brown said:

I've got a couple of pretty decent photos in my Bicycle Glossary at:

http://sheldonbrown.com/reach

I wasn't aware that this is the method for measuring reach. As shown,
it depends on pad wear and rim width. It was my understanding that
caliper reach is the vertical distance from the anchor bolt center to
the center of the brake surface on a rim. This eliminates some
undefined variables making it more generally applicable.

On the other hand, pad wear, particularly with dual pivot, centerpull
and cantilever brakes, is more strongly affected by pad wear than
prior single pivot brakes.

Jobst Brandt
[email hidden]

jobst brandt said:

Sheldon Brown said:

I've got a couple of pretty decent photos in my Bicycle Glossary at:

http://sheldonbrown.com/reach

I wasn't aware that this is the method for measuring reach. As shown,
it depends on pad wear and rim width. It was my understanding that
caliper reach is the vertical distance from the anchor bolt center to
the center of the brake surface on a rim.

Wouldn't this make "caliper reach" independent of the calipers?

--
Benjamin Lewis

I regret to say that we of the FBI are powerless to act in cases of
oral-genital intimacy, unless it has in some way obstructed interstate
commerce. -- J. Edgar Hoover

Benjamin Lewis said:

Quoted message said:

Quoted message said:

I've got a couple of pretty decent photos in my Bicycle Glossary at:

http://sheldonbrown.com/reach

Quoted message said:

Quoted message said:

I wasn't aware that this is the method for measuring reach. As
shown, it depends on pad wear and rim width. It was my
understanding that caliper reach is the vertical distance from the
anchor bolt center to the center of the brake surface on a rim.

Quoted message said:

Wouldn't this make "caliper reach" independent of the calipers?

Yes, the required reach IS independent of the brake. Then you need to
find a brake that has enough reach. I think that was the initial
problem.

Quoted message said:

I regret to say that we of the FBI are powerless to act in cases of
oral-genital intimacy, unless it has in some way obstructed
interstate commerce. -- J. Edgar Hoover

.... except that he relentlessly pursued his "enemies", for exactly
that kind of intimacy, into their bedrooms.

Jobst Brandt
[email hidden]

ah humour. anyone have a nude image of tammy?

I said:

Quoted message said:

Quoted message said:

>I've got a couple of pretty decent photos in my Bicycle Glossary at:
>
>http://sheldonbrown.com/reach

An anonymous poster asked:

Quoted message said:

Sheldon: This doesn't seem at all right. If I measure a centerpull in
this manner the numbers are way off. OTOH, If I draw a horizontal line
through the center of the mounting bolt and one through the bottom of
the brake shoe in the lowest position, then measure in between them,
it's fairly close to the spec of "610" or "750"

Are you sure about this way of measuring a sidepull ?

That lines up with the reach marked on Shimano sidepulls.

In the case of the Weinmann/Diacompe "610" and "750", those are _model_
numbers not reach dimensions.

Sheldon "Reach" Brown
+-------------------------------------------------+
| One measurement is worth 50 expert opinions |
| --Howard Sutherland |
+-------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

I write:

Quoted message said:

Quoted message said:

I've got a couple of pretty decent photos in my Bicycle Glossary at:

http://sheldonbrown.com/reach

Jobst replies:

Quoted message said:

I wasn't aware that this is the method for measuring reach. As shown,
it depends on pad wear and rim width.

Yes, it does. I generally measure with new pads, as the manufacturers do.

Quoted message said:

It was my understanding that
caliper reach is the vertical distance from the anchor bolt center to
the center of the brake surface on a rim. This eliminates some
undefined variables making it more generally applicable.

Actually it doesn't, it _introduces_ an undefined variable. The rim
width is one of the factors that helps determine the caliper reach
required.

This way is also much easier to measure, as a practical matter.

Quoted message said:

On the other hand, pad wear, particularly with dual pivot, centerpull
and cantilever brakes, is more strongly affected by pad wear than
prior single pivot brakes.

There's no arguing with that...

Sheldon "Tautology" Brown
+------------------------------------------------------------------+
| Honestly, I think we should just trust our president in every |
| decision that he makes and we should just support that. |
| -- Britney Spears, September 4, 2003 |
+------------------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

Quoted message said:

ah humour. anyone have a nude image of tammy?

By this you mean without facial makeup?

--
Tom Sherman - Earth

Tom Sherman said:

Quoted message said:

ah humour. anyone have a nude image of tammy?

By this you mean without facial makeup?

I can only hope that's what he means... shudder....

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $695 ti frame