cantilever brake problem

If you measure them, how different is the diameter?
I've seen ones that are very slightly out of spec, as in a couple of
hundreths of a mm. Different brake sleeves are machined slightly
differently as well, the same for a lot of parts like this, such as
headsets, etc.
I've fixed the above problem with slight difference with a couple of swipes
using some emery paper.

-pete

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

Quoted message said:

I just got an older mountain bike that needed new brakes.
It seems that the rear posts (the braze ons) are slightly larger than
standard. They are large than the posts for the front fork and all
the brakes that I have tried.

I don't have a lot of experience with this, but this seemed odd. Are
there different brakes that require (or allow) a larger post?

Thanks,
m

Matty Messinger said:

I just got an older mountain bike that needed new brakes.
It seems that the rear posts (the braze ons) are slightly larger than
standard. They are large than the posts for the front fork and all
the brakes that I have tried.

I don't have a lot of experience with this, but this seemed odd. Are
there different brakes that require (or allow) a larger post?

Are the posts above or below the rim? In the late '80s there was a fad
for "U-brakes" which mounted outside the rim, and I believe they used a
thicker post as well.

You can still get U brakes, they remain popular for BMX Freestyle.

Sheldon "Ancient History" Brown
+----------------------------------------------------------------+
| People are more violently opposed to fur than leather |
| Becaue it’s safer to harass rich women than motorcycle gangs |
+----------------------------------------------------------------+
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

Matty Messinger said:

I just got an older mountain bike that needed new brakes.
It seems that the rear posts (the braze ons) are slightly larger than
standard. They are large than the posts for the front fork and all
the brakes that I have tried.

I don't have a lot of experience with this, but this seemed odd. Are
there different brakes that require (or allow) a larger post?

Thanks,
m

If this is a frame with 9mm U-brake posts you could probably fit Magura
hydraulic brakes (adapters upside down) with a coupla strokes of a file.
(now isn't that a nice excuse 😉)

OTOH it is quite common to find cantiposts where the ends are slightly
mushroomed. These can be filed back to fit
--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

Matty Messinger said:

I just got an older mountain bike that needed new brakes.
It seems that the rear posts (the braze ons) are slightly larger than
standard. They are large than the posts for the front fork and all
the brakes that I have tried.

I don't have a lot of experience with this, but this seemed odd. Are
there different brakes that require (or allow) a larger post?

Are they above the rim? That's a mount for a UBrake or an
ABrake

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

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

Matty Messinger said:

I just got an older mountain bike that needed new brakes.
It seems that the rear posts (the braze ons) are slightly larger than
standard. They are large than the posts for the front fork and all
the brakes that I have tried.

I don't have a lot of experience with this, but this seemed odd. Are
there different brakes that require (or allow) a larger post?

Are the posts above or below the rim? In the late '80s there was a fad
for "U-brakes" which mounted outside the rim, and I believe they used a
thicker post as well.

You can still get U brakes, they remain popular for BMX Freestyle.

Sheldon "Ancient History" Brown
+----------------------------------------------------------------+
| People are more violently opposed to fur than leather |
| Becaue it’s safer to harass rich women than motorcycle gangs |
+----------------------------------------------------------------+
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

Another telltale location; U-brakes are typically located on the chainstay,
instead of the canti's seatstay mounting point.

David