At 7:22 PM -0700 3/26/08, Jerome & Elizabeth Moos wrote:
>These would be Racer brakes, earlier than 1970. How much earlier,
>I'm not sure, but in the mid-60's PX-10's came with these "Dural
> Jerry Moos
> Big Spring, Texas, USA
> If a set of brakes from MAFAC is stamped, simply: Dural-Forge and
>MAFAC, but no other stamp, where does that put such a brake in the
>line? Older, newer? Better, worse? Same as a Racer but without the
Jerome is correct. Mafac Racer brakes were introduced in 1952, but since Mafac did not produce any other centerpulls, they did not need to put the model name on the brake. So the arms were just stamped "Dural Forge" to highlight that they were forged, not cast or stamped, and of a high-grade alloy.
The earliest designs had slightly different arms (see for example, the bike on p. 122 of The Golden Age of Handbuilt Bicycles), but by about 1955 (and perhaps a bit earlier), the final arm shape had arrived. These usually had bronze bushings, although I have seen some late ones with plastic bushings. In the 1960s and early 1970s, Mafac introduced a plethora of centerpull models (Raid, Tiger, Top 63, Competition, 2000 come to mind), so they apparently felt the need to identify the brakes with stamped model names.
So your brakes date from sometime between 1955 and 1970. Toward 1970, if the bushings are plastic.
By the way, perhaps because of an old article of mine in the Rivendell Reader, many people feel that the later plastic bushings are inferior to the earlier bronze ones. That does not appear to be the case - the earlier bronze bushings do wear, whereas the plastic ones appear to be more resistant. I have ridden extensively on bikes with both, and can't feel a difference. My daily rider, a 1973 Alex Singer, has the plastic-bushing Racers, and they brake as well or better than any brake I have used.
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