Being a tandem enthusiast here are a few lesser known tandem brands we have ridden in the past 37 years:
Gottfried (French), Colin Laing (US and England), Follis (French), Assenmacher (US), Berry (US), Borthwick (US) Bruni (US), Counrterpoint (US), Jack Taylor (England), Lippy (US), Osell (US), Velo Schauff (Germany), Dawes (England), Fuji (Japan), Gilmour (US), Ibis (US), Montague (US), Zona (US) . . . among others.
Have owned and extensively ridden following tandems: Follis, Assenmacher, Colin Laing, Co-Motion and Zona.