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Hope this annum's Palma sojourn free of any impromptu inland waterways.
Given date would expect an oem stern spacing of one-two-six.
This means gear block would have been either a conventional six or a narrow seven.
(Slightly) puzzled by presence of braze-on for mech anteriore.
With chainstays this short one gets into crossover binding problems rather quickly.
Many frames of this pattern were conceived by their builders to be of a single plateau drive.
Conceivable front mech braze-on may be a post-manufacture addition, along with seat tube w/b.
If we take a narrow seven gear block as an example the rider would likely have had only four usable gears with the small c/w and four with the large. Yielding only eight usable combinations out of a nominal fourteen.
One maker who produced framesets of similar pattern was HARAL of France (Haute-Savoie, up against the CH border). Their design included a curved top tube. Have a few images of these saved on me hd but am away from "the ranch" this week. Shall essay their erection
semana prossima.
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