This is a new one on me:
http://cgi.ebay.fr/demultiplicateur-de- ... 0541631817
It appears to be a bottom-bracket mounted gearbox in the Schlumpf vein, but I've no idea how it operates or who made it. The cranks and rings are obviously TA. Any ideas?
If it's just a step-down gearbox, the ratios mentioned would give the equivalent of 50t and 38t with the chainrings as supplied.
Calmes dans le demi-jour
Que les branches hautes font,
Pénétrons bien notre amour
De ce silence profond.