Metal Particles in Brake Blocks

MSA said:

I was riding my new Winter training bike yesterday (in the rain!) when I
noticed that the brake blocks were making a real 'scraping' sound every
time they were applied. The noise was the sort of thing that you get
when riding in dirty conditions, but it didn't clear.

I came home and cleaned the rims but the noise was still there. I took
off a brake block and notice shiny particles in it, which wouldn't
budge. I took out my Dremmel hobby drill and ground away at the bblock
surface and uncovered metal particles set in the rubber...pretty evenly
spread across the block. All other brake blocks were the same. I
couldn't dig out the pieces with a pin or a knife so I spent some time
with the little drill and ground them out.

I've been out on the bike today and everything is fine.

Now, I've only ever used Campag brake blocks and Salmon Cool-Stops
before, and have never experienced anything like this. The brakes are
Ambrosio (deep drop) the block have no name on them so I guess they are
a generic make for calipers such as Ambrosio.

Any idea what this is all about??? Is it a manufacturing defect?

You need harder brake pads. The metal is aluminium from your rims.

MSA wrote:
/snip

Quoted message said:

Now, I've only ever used Campag brake blocks and Salmon Cool-Stops
before, and have never experienced anything like this. The brakes are
Ambrosio (deep drop) the block have no name on them so I guess they
are a generic make for calipers such as Ambrosio.

Any idea what this is all about??? Is it a manufacturing defect?

I suggest getting some Kool Stops for this bike as well. They're less prone
to ripping up rims and picking up the pieces, though it does still happen
occasionally. Maybe the model/condition of rim makes a difference? Unlike
you, I have had the problem Campag blocks.

This is only a guess but I think once the block gets pitted (from the
particles), the problem only gets worse. Blocks can be sanded to "start
again" with level surfaces.

~PB

In article <[email hidden]>, p@melonbiggs{remove says...

Quoted message said:

MSA wrote:
/snip

Quoted message said:

Now, I've only ever used Campag brake blocks and Salmon Cool-Stops
before, and have never experienced anything like this. The brakes are
Ambrosio (deep drop) the block have no name on them so I guess they
are a generic make for calipers such as Ambrosio.

Any idea what this is all about??? Is it a manufacturing defect?

I suggest getting some Kool Stops for this bike as well. They're less prone
to ripping up rims and picking up the pieces, though it does still happen
occasionally. Maybe the model/condition of rim makes a difference? Unlike
you, I have had the problem Campag blocks.

This is only a guess but I think once the block gets pitted (from the
particles), the problem only gets worse. Blocks can be sanded to "start
again" with level surfaces.

~PB

The rims are Mavic Open Pro's, and from one of my other bikes. They are
about 12 months old and never had any problems like that at all. I
think I will fit another set of Kool-Stops...is there a vendor in the UK
yet? the last ones I bought from Harris/Sheldon.

--
Mark (MSA)
This post is packaged by intellectual weight, not volume. Some settling
of contents may have occurred during transmission

MSA [email hidden] opined the following...

Quoted message said:

The rims are Mavic Open Pro's, and from one of my other bikes. They are
about 12 months old and never had any problems like that at all. I
think I will fit another set of Kool-Stops...is there a vendor in the UK
yet? the last ones I bought from Harris/Sheldon.

I've just bought several sets of road inserts from Wiggle. They seem to
have a pretty good range.

Jon

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

Quoted message said:

I was riding my new Winter training bike yesterday (in the rain!) when I
noticed that the brake blocks were making a real 'scraping' sound every
time they were applied. The noise was the sort of thing that you get
when riding in dirty conditions, but it didn't clear.

I came home and cleaned the rims but the noise was still there. I took
off a brake block and notice shiny particles in it, which wouldn't
budge. I took out my Dremmel hobby drill and ground away at the bblock
surface and uncovered metal particles set in the rubber...pretty evenly
spread across the block. All other brake blocks were the same. I
couldn't dig out the pieces with a pin or a knife so I spent some time
with the little drill and ground them out.

I've been out on the bike today and everything is fine.

Now, I've only ever used Campag brake blocks and Salmon Cool-Stops
before, and have never experienced anything like this. The brakes are
Ambrosio (deep drop) the block have no name on them so I guess they are
a generic make for calipers such as Ambrosio.

Any idea what this is all about??? Is it a manufacturing defect?

TIA.

I had this problem with Shimano M System inserts. No problem since changing
to Aztec .

MSA said:

The rims are Mavic Open Pro's, and from one of my other bikes. They
are about 12 months old and never had any problems like that at all.
I
think I will fit another set of Kool-Stops...is there a vendor in the
UK
yet? the last ones I bought from Harris/Sheldon.

See the "Recommend brake blocks" thread for Wiggle links.

~PB

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

Quoted message said:

I was riding my new Winter training bike yesterday (in the rain!) when I
noticed that the brake blocks were making a real 'scraping' sound every
time they were applied. The noise was the sort of thing that you get
when riding in dirty conditions, but it didn't clear.

I came home and cleaned the rims but the noise was still there. I took
off a brake block and notice shiny particles in it, which wouldn't
budge. I took out my Dremmel hobby drill and ground away at the bblock
surface and uncovered metal particles set in the rubber...pretty evenly
spread across the block. All other brake blocks were the same. I
couldn't dig out the pieces with a pin or a knife so I spent some time
with the little drill and ground them out.

I've been out on the bike today and everything is fine.

Now, I've only ever used Campag brake blocks and Salmon Cool-Stops
before, and have never experienced anything like this. The brakes are
Ambrosio (deep drop) the block have no name on them so I guess they are
a generic make for calipers such as Ambrosio.

Any idea what this is all about??? Is it a manufacturing defect?

Modolos came with "sinterized" blocks - is this what you have?

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

Modolos came with "sinterized" blocks - is this what you have?

Err, never heard of these so I have no idea!

--
Mark (MSA)
This post is packaged by intellectual weight, not volume. Some settling
of contents may have occurred during transmission

In article <[email hidden]>, p@melonbiggs{remove says...

Quoted message said:

MSA said:

The rims are Mavic Open Pro's, and from one of my other bikes. They
are about 12 months old and never had any problems like that at all.
I
think I will fit another set of Kool-Stops...is there a vendor in the
UK
yet? the last ones I bought from Harris/Sheldon.

See the "Recommend brake blocks" thread for Wiggle links.

~PB

Well I never, excellent!

Now all I have to do is work out what ones fit! My shoes do not look
like Campag fitting, they have a small Allen bolt at each end.

Any ideas how I can find out what type I need to buy?

--
Mark (MSA)
This post is packaged by intellectual weight, not volume. Some settling
of contents may have occurred during transmission

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

Quoted message said:

I was riding my new Winter training bike yesterday (in the rain!) when I
noticed that the brake blocks were making a real 'scraping' sound every
time they were applied. The noise was the sort of thing that you get
when riding in dirty conditions, but it didn't clear.

I came home and cleaned the rims but the noise was still there. I took
off a brake block and notice shiny particles in it, which wouldn't
budge. I took out my Dremmel hobby drill and ground away at the bblock
surface and uncovered metal particles set in the rubber...pretty evenly
spread across the block. All other brake blocks were the same. I
couldn't dig out the pieces with a pin or a knife so I spent some time
with the little drill and ground them out.

I've been out on the bike today and everything is fine.

Now, I've only ever used Campag brake blocks and Salmon Cool-Stops
before, and have never experienced anything like this. The brakes are
Ambrosio (deep drop) the block have no name on them so I guess they are
a generic make for calipers such as Ambrosio.

Any idea what this is all about??? Is it a manufacturing defect?

The problem is that the blocks pick up tiny particles of road grit, which
then grind away at your aluminium rims, and once the aluminium from the rim
becomes embedded in the block, it picks up even more, in a self-reinforcing
cycle.

This is much worse in the rain, not sure why, but it is. Perhaps there is
more grit floating around in the water, so the blocks pick up more?

Quoted message said:

TIA.

--
Mark (MSA)
This post is packaged by intellectual weight, not volume. Some settling
of contents may have occurred during transmission

MSA [email hidden] opined the following...

Quoted message said:

Well I never, excellent!

Now all I have to do is work out what ones fit! My shoes do not look
like Campag fitting, they have a small Allen bolt at each end.

Any ideas how I can find out what type I need to buy?

Got a digital camera? Post some photos on the web and send us the link.
I'm sure there'll be someone here who can ID them.

Jon

MSA said:

Now all I have to do is work out what ones fit! My shoes do not look
like Campag fitting, they have a small Allen bolt at each end.

Any ideas how I can find out what type I need to buy?

Sorry I don't know what brakes you have exactly.

Kool Stop "Dura" shoes fit most calipers (it's probably worth changing the
whole shoes even if yours take pad refills: the Kool Stop hardware is very
good). Might as well give those a go. You could always sell them on via
this group if they don't fit.

~PB