How long should caliper brake springs last?

On 2017-07-27 07:08, AMuzi wrote:
On 7/27/2017 8:30 AM, wrote:
On Wednesday, July 26, 2017 at 7:21:03 PM UTC-7, AMuzi wrote:
On 7/26/2017 7:05 PM, Sir Ridesalot wrote:
On Wednesday, July 26, 2017 at 7:40:49 PM UTC-4, sms wrote:
The brakes on my Specialized road bike were not opening all the way
when
releasing the brake levers. At first I thought it was the old brake
cables having corrosion so I replace them, and I also put on a set of
new/used levers, since the springs in the original levers were
weak, but
this wasn't sufficient.

Snipped
How often should I have to replace brake springs. Since this road
bicycle is about 30 years old I figure that the springs do fatigue
over
time.

I think this is what I wanted:
http://www.ebay.com/itm/DIA-COMPE-S-PULL-BRAKE-PART-SPRING-/282571492776?hash=item41ca92cda8:g:LiIAAOSwUFtZaPk c


How often? NEVER! Just unhook each side of the spring from the
caliper arm and then bend the brake spring upwards away from the
caliper arm to increase the tension of the spring and you'd be set
for many more years of use. The shop ripped you off by selling you
new brake calipers you did NOT need.


Right. Besides which the most common problems are dirt/crud
or a bent inner arm.
Dissassemble, clean everything, oil or grease all mating
parts and reassemble such that arms move freely without any
fore/aft slop. Lock adjustment, hook the spring ends in and
you're good for many years.
Bent arms on that class of brake are very easily reshaped.
Hold in aluminum vise jaws, rectify with a crescent wrench
and a straightedge.

Wouldn't you think that after 30 years that it is likely that the
spring is rusted and dragging against itself? If you clean the spring
of it's rust you still have the pitting which reduces the action of
the spring.


In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.


I second that. The springs on my 1982 Shimano 600 set feel like they
always did. That bike has seen a lot of miles in hilly areas where I was
in the brakes all the time.

Things do need to be lubed from time to time. I also have to
"de-mud-cake" the works a lot when it hardens after going on dirt roads
in wet weather. Sometimes I take brakes and such apart and brown dried
dust sails to the floor.

--
Regards, Joerg

http://www.analogconsultants.com/

On Thu, 27 Jul 2017 09:57:44 -0700, sms
wrote:

On 7/27/2017 7:08 AM, AMuzi wrote:

snip

In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.

The spring is not rusty. But it pops out with no effort, it's just not
springy anymore. It seems to be fatigued.

The brake sets are cleaned and lubed. I may still order some springs to
use these brakes on another road bike which has lower quality brakes. If
I were in Wisconsin, I'm sure that AMuzi would have the springs in
stock, but the shops in Silicon Valley have little interest in stocking
and selling little parts like this.


Probably because no one but you ever wanted to buy any :-(
--
Cheers,

John B.

On 7/27/2017 8:40 PM, John B. Slocomb wrote:
On Thu, 27 Jul 2017 09:57:44 -0700, sms
wrote:

On 7/27/2017 7:08 AM, AMuzi wrote:

snip

In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.

The spring is not rusty. But it pops out with no effort, it's just not
springy anymore. It seems to be fatigued.

The brake sets are cleaned and lubed. I may still order some springs to
use these brakes on another road bike which has lower quality brakes. If
I were in Wisconsin, I'm sure that AMuzi would have the springs in
stock, but the shops in Silicon Valley have little interest in stocking
and selling little parts like this.


Probably because no one but you ever wanted to buy any :-(

https://www.teachengineering.org/les...cancer_lesson2

"... structural materials that are able to safely endure
everyday stress while remaining in the elastic region of the
stress-strain curve, otherwise permanent deformation occurs..."

For single pivot bicycle brake springs, simply reshaping a
damaged spring by holding the center section in a vise and
moving the ends to a symmetric shape is straightforward and
simple.


--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Wednesday, July 26, 2017 at 7:40:49 PM UTC-4, sms wrote:
The brakes on my Specialized road bike were not opening all the way when
releasing the brake levers. At first I thought it was the old brake
cables having corrosion so I replace them, and I also put on a set of
new/used levers, since the springs in the original levers were weak, but
this wasn't sufficient.

Went to a bike shop this morning and the shop was closed but the service
area had an open door and I asked the mechanic about replacement
springs. These are for Dia-Compe Edge brakes that came with the bicycle,
circa 1987.

The mechanic told me to just replace the brake set. I ended up buying a
set of Ultegra 6800 calipers from him, with pads, that he had taken off
a bicycle where the owner was upgrading. At first he wanted to sell me
the whole Ultegra group for $300, which had a FC-6703 triple crank, but
he sold me the brakes only, for $50. This is a much better brakeset than
the original, but really I only needed the springs, I was just in a hurry..

How often should I have to replace brake springs. Since this road
bicycle is about 30 years old I figure that the springs do fatigue over
time.

I think this is what I wanted:
http://www.ebay.com/itm/DIA-COMPE-S-PULL-BRAKE-PART-SPRING-/282571492776?hash=item41ca92cda8:g:LiIAAOSwUFtZaPk c

the bores/pistons are worn out of round ...not changing fluid over time is one

cause in auto. Piston position goes up one end down other causing snubbing. prob not the spring ...spring are cushion not a ram.

in auto, come x miles, you toss the lot n get new or in drums tinker tinker tinker. Iam for reasons of preventive maint...new to discs....major improvement over servicing drums. The four huge abs discs on muh E250 are a source of wonder leading to thoughts of GT40's glowing in the dark at the end of the straight.

On 7/27/2017 6:40 PM, John B. Slocomb wrote:
On Thu, 27 Jul 2017 09:57:44 -0700, sms
wrote:

On 7/27/2017 7:08 AM, AMuzi wrote:

snip

In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.

The spring is not rusty. But it pops out with no effort, it's just not
springy anymore. It seems to be fatigued.

The brake sets are cleaned and lubed. I may still order some springs to
use these brakes on another road bike which has lower quality brakes. If
I were in Wisconsin, I'm sure that AMuzi would have the springs in
stock, but the shops in Silicon Valley have little interest in stocking
and selling little parts like this.


Probably because no one but you ever wanted to buy any :-(

Yet they are available online, so clearly someone has wanted them, and
there are instructions online that refer to the need to replace weak
springs.

AMuzi shows them he http://www.yellowjersey.org/dcbitz.html

On Mon, 31 Jul 2017 14:50:53 -0700, sms
wrote:

On 7/27/2017 6:40 PM, John B. Slocomb wrote:
On Thu, 27 Jul 2017 09:57:44 -0700, sms
wrote:

On 7/27/2017 7:08 AM, AMuzi wrote:

snip

In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.

The spring is not rusty. But it pops out with no effort, it's just not
springy anymore. It seems to be fatigued.

The brake sets are cleaned and lubed. I may still order some springs to
use these brakes on another road bike which has lower quality brakes. If
I were in Wisconsin, I'm sure that AMuzi would have the springs in
stock, but the shops in Silicon Valley have little interest in stocking
and selling little parts like this.


Probably because no one but you ever wanted to buy any :-(

Yet they are available online, so clearly someone has wanted them, and
there are instructions online that refer to the need to replace weak
springs.

AMuzi shows them he http://www.yellowjersey.org/dcbitz.html

So what? The point was to respond to your statement that, "the shops
in Silicon Valley have little interest in stocking and selling little
parts like this", and I would bet money on my statement that it was
that "Probably because no one but you ever wanted to buy any".

The argument has nothing to do with what is available on line or what
Andrew stocks, but what the demand is in Silicon Valley".
--
Cheers,

John B.

On Monday, July 31, 2017 at 6:10:42 PM UTC-7, John B. wrote:
On Mon, 31 Jul 2017 14:50:53 -0700, sms
wrote:

On 7/27/2017 6:40 PM, John B. Slocomb wrote:
On Thu, 27 Jul 2017 09:57:44 -0700, sms
wrote:

On 7/27/2017 7:08 AM, AMuzi wrote:

snip

In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.

The spring is not rusty. But it pops out with no effort, it's just not
springy anymore. It seems to be fatigued.

The brake sets are cleaned and lubed. I may still order some springs to
use these brakes on another road bike which has lower quality brakes. If
I were in Wisconsin, I'm sure that AMuzi would have the springs in
stock, but the shops in Silicon Valley have little interest in stocking
and selling little parts like this.


Probably because no one but you ever wanted to buy any :-(

Yet they are available online, so clearly someone has wanted them, and
there are instructions online that refer to the need to replace weak
springs.

AMuzi shows them he http://www.yellowjersey.org/dcbitz.html

So what? The point was to respond to your statement that, "the shops
in Silicon Valley have little interest in stocking and selling little
parts like this", and I would bet money on my statement that it was
that "Probably because no one but you ever wanted to buy any".

The argument has nothing to do with what is available on line or what
Andrew stocks, but what the demand is in Silicon Valley".

You've been pretty snippy lately John. Is it your time of the month?

On 7/31/2017 5:50 PM, sms wrote:
On 7/27/2017 6:40 PM, John B. Slocomb wrote:
On Thu, 27 Jul 2017 09:57:44 -0700, sms
wrote:

On 7/27/2017 7:08 AM, AMuzi wrote:

snip

In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.

The spring is not rusty. But it pops out with no effort, it's just not
springy anymore. It seems to be fatigued.

The brake sets are cleaned and lubed. I may still order some springs to
use these brakes on another road bike which has lower quality brakes. If
I were in Wisconsin, I'm sure that AMuzi would have the springs in
stock, but the shops in Silicon Valley have little interest in stocking
and selling little parts like this.


Probably because no one but you ever wanted to buy any :-(

Yet they are available online, so clearly someone has wanted them, and
there are instructions online that refer to the need to replace weak
springs.

There are? Where?

AMuzi shows them he http://www.yellowjersey.org/dcbitz.html

By that argument, people must have to replace flat-concave mounting
washers too. Metal fatigue, is it?

--
- Frank Krygowski

On Mon, 31 Jul 2017 18:29:23 -0700 (PDT), wrote:

On Monday, July 31, 2017 at 6:10:42 PM UTC-7, John B. wrote:
On Mon, 31 Jul 2017 14:50:53 -0700, sms
wrote:

On 7/27/2017 6:40 PM, John B. Slocomb wrote:
On Thu, 27 Jul 2017 09:57:44 -0700, sms
wrote:

On 7/27/2017 7:08 AM, AMuzi wrote:

snip

In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.

The spring is not rusty. But it pops out with no effort, it's just not
springy anymore. It seems to be fatigued.

The brake sets are cleaned and lubed. I may still order some springs to
use these brakes on another road bike which has lower quality brakes. If
I were in Wisconsin, I'm sure that AMuzi would have the springs in
stock, but the shops in Silicon Valley have little interest in stocking
and selling little parts like this.


Probably because no one but you ever wanted to buy any :-(

Yet they are available online, so clearly someone has wanted them, and
there are instructions online that refer to the need to replace weak
springs.

AMuzi shows them he http://www.yellowjersey.org/dcbitz.html

So what? The point was to respond to your statement that, "the shops
in Silicon Valley have little interest in stocking and selling little
parts like this", and I would bet money on my statement that it was
that "Probably because no one but you ever wanted to buy any".

The argument has nothing to do with what is available on line or what
Andrew stocks, but what the demand is in Silicon Valley".

You've been pretty snippy lately John. Is it your time of the month?

Well, I admit that I have very little time for SMS, but I still
contend that if sufficient people were to walk into Silicon Valley
bicycle shops wanting replacement brake springs that even a
Californian would be able to figure out that there was a market for
brake springs and would stock them.
--
Cheers,

John B.

On 8/1/2017 12:42 AM, John B. wrote:
On Mon, 31 Jul 2017 18:29:23 -0700 (PDT), wrote:

On Monday, July 31, 2017 at 6:10:42 PM UTC-7, John B. wrote:
On Mon, 31 Jul 2017 14:50:53 -0700, sms
wrote:

On 7/27/2017 6:40 PM, John B. Slocomb wrote:
On Thu, 27 Jul 2017 09:57:44 -0700, sms
wrote:

On 7/27/2017 7:08 AM, AMuzi wrote:

snip

In theory maybe but I've never seen that in real life. Rust is ugly but
in terms of % reduction of cross section of a spring, it's meaningless.

The spring is not rusty. But it pops out with no effort, it's just not
springy anymore. It seems to be fatigued.

The brake sets are cleaned and lubed. I may still order some springs to
use these brakes on another road bike which has lower quality brakes. If
I were in Wisconsin, I'm sure that AMuzi would have the springs in
stock, but the shops in Silicon Valley have little interest in stocking
and selling little parts like this.


Probably because no one but you ever wanted to buy any :-(

Yet they are available online, so clearly someone has wanted them, and
there are instructions online that refer to the need to replace weak
springs.

AMuzi shows them he http://www.yellowjersey.org/dcbitz.html

So what? The point was to respond to your statement that, "the shops
in Silicon Valley have little interest in stocking and selling little
parts like this", and I would bet money on my statement that it was
that "Probably because no one but you ever wanted to buy any".

The argument has nothing to do with what is available on line or what
Andrew stocks, but what the demand is in Silicon Valley".

You've been pretty snippy lately John. Is it your time of the month?

Well, I admit that I have very little time for SMS, but I still
contend that if sufficient people were to walk into Silicon Valley
bicycle shops wanting replacement brake springs that even a
Californian would be able to figure out that there was a market for
brake springs and would stock them.


Riders do indeed replace brake springs as part of
clean/shine/polish/wax and throw out rusted bits. A bicycle
brake spring can't travel beyond elastic limits unless it is
removed from the brake:

https://www.britannica.com/science/elastic-limit

Which Frank noted earlier.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971