MAFACs have the virtue of being widely available (cannibalized off 70s 
bikes, if nothing else) and therefore cheap. If you have none of your own, 
and there's no abandoned 70s bikes out on the sidewalk in your area to 
cannibalize, your town is between Princeton and Trenton; surely they have 
community bike shops with scavenged components.

Paul centerpulls (which they're apparently making in both original 
<https://www.paulcomp.com/shop/components/brakes/center-pull-brakes/racer/> 
and "medium" 
<https://www.paulcomp.com/shop/components/brakes/center-pull-brakes/racer-medium/>
 
style again, after discontinuing them for a while a couple of years ago) 
use the same pivot post diameter as MAFAC centerpulls; it's that: 1) Paul's 
centerpull/canti pivots are longer than normal centerpull pivots, to 
accommodate the  pivot booster and 2)  centerpull posts have a different 
placement from cantilever posts*.

So you can't mount Paul centerpulls on posts for cantilever brakes, and 
vice versa. I'm unclear what would happen if you tried to mount Paul 
calipers on standard-length posts; personally, I'd want to phone Paul and 
talk to a person who could tell me, before committing $300+ to a brakeset.

Usually, the spacing between the posts is also wrong for switching brake 
designs, and this is a place where the selection of centerpull brake comes 
into play. The spacing between all the non-RAID MAFAC models is 62-83 mm 
C-C, while the 650B-centric RAID is 75 mm (the adjustable reach Top 63 is 
73 mm, but they're very rare). Measure your posts and see what you need, 
with the understanding that there are Dia-Compes (some branded as Grand 
Bois or Rene Herse) that fit those spacings.

Here's a Google Docs spreadsheet (snitched from Bike Forums) with a 
breakdown on different centerpull models, including post diameters, post 
spacings and caliper reach:

https://docs.google.com/spreadsheets/d/1ze6QFPgZFbBQmgM8ATWDE5JStRur-Q3-Mmr4hMtclRg/edit?gid=295272010#gid=295272010

If I were in your position - well, I'd sample several of my vast hoard of 
MAFAC brakes (Dural Forge, Racer, Competition, GT, RAID) to see what fit 
the pivot posts and gave sufficient clearance for the wheels. If you have 
no such stash, local bike kitchens are the logical place to find 
candidates. Find out if there's a cheap salvaged brake that will work, 
before committing sizable money to new calipers; at least that way, you 
have a bailout option.

* cantilevers place the brake pads above the pivot; centerpulls place the 
pads below the pivot; to fit the same size wheel, direct mount centerpull 
pivots need to be placed higher than cantilever posts. Typically, you can 
distinguish the two post placements by the distance between the posts and 
the fork crown/rear brake bridge; centerpull posts are usually placed so 
high you couldn't mount cantilever brakes on the post at all, as the 
crown/bridge would block the pads

Peter Adler
Berkeley, CA

On Sunday, November 3, 2024 at 5:54:55 PM UTC-8 Oliver Moss wrote:

Ah, so you're the one who picked that Elephant. That looked sweet! 

On Sunday, November 3, 2024 at 6:31:37 PM UTC-5 Robert Blunt wrote:

Hello everyone,
I just snagged an elephant frame whose geometry is modeled on the NFE 
(650B), but with center pull braze ons rather than disc brakes. I am 
looking for recommendations for brakes. From what I can gather, I basically 
can have the Herse or Compass center pulls if go new, and Mafac raids if I 
go old. I think the Paul racers won’t work since they are designed around a 
different diameter braze on. I would love to know if I am wrong about this 
as Pauls would be my go to. Anyway, the Saluki was last winter’s project 
and the elephant will be this winter’s fun. Thanks in advance for any 
anecdotes about any of the first three brakes mentioned or whether Pauls 
could work.

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