From the 1977 catalog
is made up from the names of GAastra and KOwalik (his
Gaastra started importing bikes made by
He also started importing
Shimano, which business later turned into Shimano Europe. Koga
frames are now sourced elsewhere (Hodaka?) and Miyata has
A son of Gaastra has started a high end brand (Idworx & Gaastra)...
Koga is now owned by Accell.
Marten Gerritsen on
the Classic Rendezvous Google group
History on Company's web site
Catalogs from 1976
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