Originally Posted by juvela

it is difficult to tell for sure from the lo-res image but i suspect cycle frame is actually a Kalkhoff. they built with Agrati lugs, crowns, and bulge-formed heads paired with Pletscher plate style bridges. missing bb fittings may have been Thun.

here is one which looks to date from ~1972:

Amazing GERMAN1960 1970's Kalkhoff Super Sport 10 Speed Racer Bike Like Schwinn | eBay