The Belgica followed the 175 Legia, designed by Marcel Doflein. Components are from mainly German suppliers - Bing carburettors, VDB wheel hubs, Ferodo brakes, Hella & Bosch electrics.
According to a restorer, there are three different models of Belgica; the standard model has the mudguard with integrated flap and the slightly square side boxes; the semi-faired version has toolboxes with rounded shapesl and the faired model has the carburettor concealed behind an aluminum casing.
They go on to say that many parts fitted to the Belgica are the same as on the previous Legia and Milan models:
Saroléa Montana 200cc 1955 - some parts seemed to be similar between the Belgica 200cc - the front and rear hubs are almost identical as well as the rear light, the carburettor and the fork.
Sources: https://www.geocities.ws/gilletherstalbelgica/BELGICA.html, et al.
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