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Ollie O
front brake caliper definitely original
rear brake caliper definitely not
(btw it is also a 999; the red label which sat in the recess on the outer caliper arm face has gone missing; it proclaimed this information)
estimate cycle to come to us from the time window of ~1958-1963
guesstimate that earliest importation of Bergies to the U.S. would have been late 1950's
other clues to the earliness of your example in addition to the front brake caliper are the headplate and the fork
fork constructed with a track style crown and round blades with dimples on the inside for tyre clearance
you should be able to narrow the date of your example by browsing back Sears catalogues which are posted online. a Sears badged version of the Bergie was sold for a good period.
back Sears catalogues are archived online by year. suggest to begin with the year 1958; no need to look past the year 1963.
chain lacks master link because it is a derailleur chain
a master link would hang up as it went through the chain path on a derailleur geared cycle
derailleur chains come apart (and go back together) with a tool called a chain rivet press
it is likely the cycle's drive chain comes from either the firm Union Frondenberg or Wippermann
their logos look like this -
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