I just tried to mount Mafac competition brake arms on Mafac Braze-on Canti bosses (not yet brazed on), and 3 dimensions were off:
Inside spring diameter (bigger on Competition) Spring attachment point (closer to center of pivot on canti-boss) Length of boss/pivot-pin (longer on canti boss)
Several bikes in Jan's "Golden Age" book have this kind of set-up, but all seem to use custom bosses.
Does anybody know if there are special braze-on bosses for center-pull brakes?
Are they still available anywhere?
Amir Avitzur
Ramat-Gan, Israel