Peter Adler, THANK YOU! I have a fantastic mechanic up in the Water Gap who has spare Mafacs laying around (Racer and Raids) so as soon as the frame gets here, we will try every Mafac he has in stock. I think I will give Paul a call and ask them if they might work. These are definitely not canti-posts so if I were able to make the Pauls work I would invest in them. I have them on my saluki and I am pretty blown away by their power. Do you or anyone else have any experience with Dia Comp Gran Compe centerpulls? --Rob Pennington, NJ
On Mon, Nov 4, 2024 at 4:24 PM Peter Adler <divisi....@gmail.com> wrote: > 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. > > -- > You received this message because you are subscribed to the Google Groups > "RBW Owners Bunch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to rbw-owners-bunch+unsubscr...@googlegroups.com. > To view this discussion visit > https://groups.google.com/d/msgid/rbw-owners-bunch/f437a46d-b22c-4ac0-8adb-a1d538344216n%40googlegroups.com > <https://groups.google.com/d/msgid/rbw-owners-bunch/f437a46d-b22c-4ac0-8adb-a1d538344216n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/rbw-owners-bunch/CAGTQPx_A%2B_zk2VX7u48r096cFqyB-e3zRUeczXPJOwCKEKUejg%40mail.gmail.com.
