Originally Posted by
bikemig
27 zip seatpost would be an unusual size for a French or Swiss bike; 26.4 or 26.6 is common. I've seen serial numbers on the outside of the BB like that on Cilo bikes but I have no idea whether this is a Cilo. Interesting bike and worth restoring.
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crown appears if may be a Georg Fischer item
wrt 27.0mm pillar size -
possible it began life at the predictable 26.6mm size and someone has reamed it out to this size because they had a pillar of this diameter they wished to employ
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