Mafac brakes and brazed on bosses
Gary Jacobson
frame that I will have made. Brakes are a hang-up. Don't like cantilevers,
especially, nor V-brakes, and side pulls long enough to accommodate 25-28
tires and fenders are not thrilling me. Maybe if Campy made them I'd feel
different about a side pull.
So I am thinking about using something like a Mafac centerpull without the
bridge to hold the arms. I'd have bosses brazed on to fork and chain stays.
Will I need stiffer fork and stays than standard? Any one with experience
with this set up? Any problems with, or positive aspects to this plan/idea?
Would any brand centerpull fit a "standard" centerpull boss braze on. Where
Universal "better" than Mafac? ANy real difference in the various Mafac
offerings.
Many thanks.
Gary Jacobson
Rosendale, NY
Phil Brown
>especially, nor V-brakes, and side pulls long enough to accommodate 25-28
>tires and fenders are not thrilling me. Maybe if Campy made them I'd feel
>different about a side pull.
They did and they're easily available on the web and at several shops. They're
the old single pivot standard reach Record brakes. Shimano also makes a
standard reach dual pivot in two grades.
>So I am thinking about using something like a Mafac centerpull without the
>bridge to hold the arms. I'd have bosses brazed on to fork and chain stays.
Why chain stays? The pivots normally would be brazed to the seat stays. This
arrangement has been used for many years on French bikes and works very well. I
have a couple of bikes like this myself. See
www.paulstubblebine.com/philbrown
The braze on pivots will fit most centerpulls. I've used Mafac, Dia Compe and
Weinmann on the road and tested Universals. All fit. There are many differences
in Mafac brakes over the years. Best to use the regular old Racer available in
the discard brake bin at many shops because the straddle cable is easier to
find today. Others (Competition and 2000) use odd cables that are very hard to
find and hoarded by those (like me) who use them. Racers come in 4 different
reaches so you may be able to tailor it to your frame.
Phil Brown.
Gary Jacobson
I meant to say seat, not chain stay.
GJ
"Phil Brown" <philc...@aol.com> wrote in message
news:20030416111807...@mb-m15.aol.com...
Bob Taylor
rear. These brakes were originally intended for mountain bikes so
there is lots of clearance for road size tires. The biggest advantage
to me was that they don't stick out to the side like cantilever brakes
do so I don't have to move my panniers way back. U brakes are pretty
much the same as you were describing, a centerpull brake without the
bridge, they mount to braze on bosses. The bosses are not the same as
cantilever brake bosses but are available from the places that sell
frame braze ons.
The Ubrakes themselves are still made by Dia Compe and perhaps others.
Back in the 80's they Shimano and Campy make them and you could
probably find some NOS ones. I have both Campy and Shimano Ubrakes
but I don't want to sell the ones I have.
The brakes work very well and they use the same brake shoes as most
Vbrakes.
Bob Taylor
"Gary Jacobson" <gjacobson-rem...@hvc.rr.com> wrote in message news:<gC1na.75837$e8.5...@twister.nyroc.rr.com>...
Bill Putnam
> frame that I will have made. Brakes are a hang-up. Don't like cantilevers,
> especially, nor V-brakes, and side pulls long enough to accommodate 25-28
> tires and fenders are not thrilling me. Maybe if Campy made them I'd feel
> different about a side pull.
Campy did make a side pull that had adequate reach for 28 mm tires and
fenders-the old Record brakes of the 70's. There were other
manufacturers at the time that made side pull brakes that were also
quite useful-Dia Compe is one manufacturer. If you want to run 38 mm
or wider tires and fenders, then sidepulls may not be to your liking,
but the old "normal reach" 47-57 mm quality side pull brakes are quite
adequate for a loaded touring bike unless your hands are very small or
weak. New aero style levers and modern slick cables will give better
braking than original equipment for this set up.
> So I am thinking about using something like a Mafac centerpull without the
> bridge to hold the arms. I'd have bosses brazed on to fork and chain stays.
This was done on some of the high end custom touring bikes decades
ago.
> Will I need stiffer fork and stays than standard? Any one with experience
> with this set up? Any problems with, or positive aspects to this plan/idea?
> Would any brand centerpull fit a "standard" centerpull boss braze on. Where
> Universal "better" than Mafac? ANy real difference in the various Mafac
> offerings.
I don't know of any need for stiffer forks and stays than standard, as
this is similar to a cantilever set up. Perhaps it could be a concern
with some of the exotic lightweight tubing available today, but this
would be a good question for your frame builder. The Mafac center
pull brakes are known for being more flexible than others such as
Weinmann, so if you go that route you might consider using parts off
an old Weinmann brake set.
Personally I find the old Campy Record "normal" 47-57 mm reach brakes
fine for loaded touring or just about any use you might have for a
road bike using fenders with tires of 32mm width or less. They have
less of an issue of position error with brake pad wear vs. other brake
designs, and can track a bent wheel better.
See the faq
http://draco.acs.uci.edu/rbfaq/FAQ/8f.15.html
Bill Putnam
Gary Jacobson
compe seems nearly impossible. Along the idea of U brakes, I'd like to see
what the Campy OR offering looks like.
GJ
"Bill Putnam" <bpu...@ci.madison.wi.us> wrote in message
news:a5c190b0.03041...@posting.google.com...
A Muzi
news:gC1na.75837$e8.5...@twister.nyroc.rr.com...
That's been done and has an elegant look to certain old people ( me). I
have seen that done on regular metric gauge Reynolds to good effect so I
wouldn't be afraid to try it. Maybe just shoot some spray paint on the
damaged area and ride a season to see if you are happy with them before
investing in a pricey refinish service.
Mafac Racers are a bit more "open" for tire clearance than Competitions.
Classic-era Racers take a regular gear wire for the transverse wire ( except
the later double-ended-wire models which are to be avoided). Competitions
also use a hard-to-find cross wire. Universals have good clearance too but
are a more brittle material. Their cross wire interchanges with Weinmann
and those aren't too hard to find. I do not know if a Universal #61 fits a
standard "Mafac" type boss.
--
Andrew Muzi
http://www.yellowjersey.org
Open every day since 1 April 1971
Phil Brown
>standard "Mafac" type boss.
It does.
Phil Brown
Phil Brown
>pull brakes are known for being more flexible than others such as
>Weinmann, so if you go that route you might consider using parts off
>an old Weinmann brake set.
The flex comes from the bridge the arms mount on. With brazed on pivots they're
very solid.
Phil Brown
Benjamin Weiner
> I like the idea of campy "long reach" vintage calipers. Finding them or Dia
> compe seems nearly impossible. Along the idea of U brakes, I'd like to see
> what the Campy OR offering looks like.
I guess I don't understand why the current Shimano or Tektro
long reach dual pivots are objectionable. Failing that, Campy
single pivots are presumably available somewhere (ebay?) and Diacompe
500 long reach sidepulls were common as dirt on late 70s - 80s
bikes, hence still around, used. The cheapest of those have no QR,
and the better 500's have a slightly cheesy QR, but it works fine.
Diacompe and Weinmann centerpulls also have acres of tire clearance.
None of which is to discourage you from braze-ons and Mafacs if it
floats your boat. Just don't use a stamped steel front cable hanger.
Bill Putnam
...
> I guess I don't understand why the current Shimano or Tektro
> long reach dual pivots are objectionable. Failing that, Campy
> single pivots are presumably available somewhere (ebay?) and Diacompe
> 500 long reach sidepulls were common as dirt on late 70s - 80s
> bikes, hence still around, used.
At the risk of repeating myself see the FAQ
http://draco.acs.uci.edu/rbfaq/FAQ/8f.15.html
here's an excerpt from this:
"The offset arm (the short
one) sweeps its pad upward into the tire so that this pad must be
adjusted as it wears. The brake cannot track a crooked wheel with,
for instance, a broken spoke, and because it has a high ratio, it does
not work at all when the quick release is accidentally left open. And
finally, it runs out of hand lever travel 40% faster with pad wear
than the former single pivot brake. Its low pad clearance and narrow
flange spacing of current wheels make the brake drag when climbing
hills standing, so that racers often ride with the rear quick release
open."
Used Campy Record brakes come up on e bay, Dia Compe 500's can be
found regularly in the trash (at least around here) or at swap meets-I
bought a complete set of NOS Dia Compe 500G brakes a couple years ago
for $5.
Bill Putnam
Gary Young
> Benjamin Weiner <b...@babar.ucolick.org> wrote in message news:<3e9e4d87$1...@news.ucsc.edu>...
> ...
> > I guess I don't understand why the current Shimano or Tektro
> > long reach dual pivots are objectionable. Failing that, Campy
> > single pivots are presumably available somewhere (ebay?) and Diacompe
> > 500 long reach sidepulls were common as dirt on late 70s - 80s
> > bikes, hence still around, used.
>
> At the risk of repeating myself see the FAQ
>
> http://draco.acs.uci.edu/rbfaq/FAQ/8f.15.html
>
> here's an excerpt from this:
>
> "The offset arm (the short
> one) sweeps its pad upward into the tire so that this pad must be
> adjusted as it wears. The brake cannot track a crooked wheel with,
> for instance, a broken spoke, and because it has a high ratio, it does
> not work at all when the quick release is accidentally left open. And
> finally, it runs out of hand lever travel 40% faster with pad wear
> than the former single pivot brake. Its low pad clearance and narrow
> flange spacing of current wheels make the brake drag when climbing
> hills standing, so that racers often ride with the rear quick release
> open."
Yes, but the original poster said that he preferred brazed-on
centerpulls to long-reach dual pivots. On a centerpull, don't both
arms sweep their pads upward into the tire? Unless you have quick
releases at the brake lever (as on Campagnolo brakes), there is no
quick way to adjust center pulls when you break a spoke, right? I'm
not sure how centerpulls compare to dual pivots in the other respects
discussed in the FAQ, but I do think the original poster may not have
thought through the question of whether centerpulls are better than
dual pivots.
Chris Zacho The Wheelman
"So I am thinking about using something like a Mafac centerpull without
the bridge to hold the arms. I'd have bosses brazed on to fork and chain
stays."
THAT sounds like a marvelous idea, from a design standpoint. But there
has to be a reason no manufacturer has come up with it already.
Centerpulls were the most powerfull brakes going in their day, so it
seems that it would be a somewhat obvious evolutionary step.
Can't wait to hear how it comes out, if it can be done!
May you have the wind at your back.
And a really low gear for the hills!
Chris
Chris'Z Corner
"The Website for the Common Bicyclist":
http://www.geocities.com/czcorner
Phil Brown
>stays."
>
>THAT sounds like a marvelous idea, from a design standpoint. But there
>has to be a reason no manufacturer has come up with it already.
>Centerpulls were the most powerfull brakes going in their day, so it
>seems that it would be a somewhat obvious evolutionary step.
>
>Can't wait to hear how it comes out, if it can be done!
>
>May you have the wind at your back.
>And a really low gear for the hills!
>Chris
It's been done for a very long time, Chris.
Phil Brown
John Thompson
> "So I am thinking about using something like a Mafac centerpull without
> the bridge to hold the arms. I'd have bosses brazed on to fork and chain
> stays."
>
> THAT sounds like a marvelous idea, from a design standpoint. But there
> has to be a reason no manufacturer has come up with it already.
Sounds like a cantilever brake to me...
--
-John (John.T...@attglobal.net)
A Muzi
Chris Zacho "The Wheelman" wrote:
>
> > "So I am thinking about using something like a Mafac centerpull without
> > the bridge to hold the arms. I'd have bosses brazed on to fork and chain
> > stays."
> >
> > THAT sounds like a marvelous idea, from a design standpoint. But there
> > has to be a reason no manufacturer has come up with it already.
"John Thompson" <jo...@starfleet.thompson.us> wrote in message
news:slrnba2gg...@starfleet.thompson.us...
> Sounds like a cantilever brake to me...
The cantilever "cantilevers" out away from the frame, a normal centerpull's
arm crosses inside over the tire. Yes, they are quite similar - mirror or
inside-out versions of one another.
Pete Geurds
Calls for four more brazing operations requiring some level of precision.
Probably why production bikes didn't get them.
Pete
Chris Zacho The Wheelman
"It's been done for a very long time, Chris. Phil Brown"
By whom (besides custom builders). I haven't seen any of the major
manufacturers make these, Shimano, for example.
May you have the wind at your back.
And a really low gear for the hills!
Chris
Chris'Z Corner
Phil Brown
>By whom (besides custom builders). I haven't seen any of the major
>manufacturers make these, Shimano, for example.
First, Many French makers did this, not just the high end guys like Herse and
Singer. But on a more prosaic level, Centurion made such a bike, the Pro Tour
in the 80s. and the bosses I use are made by Dia compe, not a company known for
esoterica. Many bikes in Japan use braze on bosses.
Phil Brown