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if/when you are able to repack HS and BB you may be able to learn more from markings on steerer and centre section of spindle
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btw - tried searching at retrobike uk forum, as you may have done as well, only for the search engine there to state that the word has never been posted(!)
for fun, tried searching in german and dutch without success. searching in french generates returns but only because of the french brand of saddle with the name
methinketh ye ha' something rather rara avis there
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