Rear mounting for center pull was by special hanger which attached to a special boss (this was not just a drilled and tapped hole) So when bikes were "upgraded" to the Universal 61 we see creative engineering (bike mechanics were prolific tinkerers, or at least I think so) the ultimate of which was the Spivey modified Bianchi which had a drilled seat post with tiny ramp coming out the back for the cable to slide on (anyone have a photo of that?) I think the correct description of the Legnano set up was a ''Boss''
BOB FREITAS looking to be another spectacular day in MILL VALLEY, CA USA
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