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The World Championship of Cycling was won on a Bauer machine in 1952. Thereafter for many years all Bauer cycles bore a transfer proclaiming "WELTMEISTER 1952."
Company was based in Starkenburg, Germany (DBR). IIRC production ceased in the mid--1960's. They were one of the few German producers who offered first quality lighweight sports cycles.
Lugs almost look like they could be one of the patterns from Dusika (Austria).
German catalogue page of 1959 --
The lugset on this distaffer of 1950 looks to bear a close familial relation to that of our subject machine -
https://www.steel-vintage.com/bauer-ladies-roadbike-1950s-detail
Fork crown appears to be wearing a cap of stamped aluminum sheet. Is that correct?
The Pletscher is curious in that it appears to have been produced for mounting to a small wheeled machine and has adaptors added to make its deck come out parallel to the ground on a cycle with full sized wheels.
Finish - should you wish to explore the bicycle's livery original one spot which offers a good liklihood of clues is the steerer. There may be yet some colour there from the factory spray application. Another place to examine in this regard is the interior of the bottom bracket shell.
Readers might be able to write more if they could see some images of the complete bicycle. Very few of the fittings appear to be original which makes model and date identification more difficult.
In case you think of searching on the Altenburger name it is spelt with a u rather than with an e. The company is best known for caliper brake products but produced other componentry as well. Even derailleurs. In the late 1940's they joined forces with two other component makers to offer a road ensemble which enjoyed but a brief production life.
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