Originally Posted by bulgie

They also made one to take two freewheel sprockets to turn your crank into a quad. Not very popular since most F.der.s can't shift 4 chainrings. Somebody (maybe as a joke) set one up as a quint:



Could work well as the captain's crank on a front-drive tandem, with a custom or modified F.der., like Routens and so many other Frenchies did back in the '40s-'50s. Didn't Jan Heine make one recently?