This is a workable copy of a 1950s Campagnolo Gran Sport. Even the details are pretty correct except for the pulley cage plates - which have strange and function-free extra struts.

This Ludoal Gran Sport is extremely similar to some Gambato Gran Sports - but their are significant differences:

• On the Ludoal the main Allen bolts at the b-pivot and the p-pivot are very like the Campagnolo design - which is not true of the Gambatos.
• The Campagnolo has a 43mm pulley cage, this Ludoal has a 44mm pulley cage and the Gambatos has a 45mm pully cage. Why? Who can say.

• Derailleur brands: Ludoal
• Country: Argentina
• Date of introduction: 1967?
• Date of this example: unknown
• Model no.: unknown
• Weight: 290g
• Maximum cog: 32 teeth (Campagnolo’s unlikely figure for the Gran Sport)
• Total capacity: 26 teeth
• Pulley centre to centre: 44mm
• Index compatibility: friction
• Chain width: 3/32”
• Logic: top normal
• B pivot: unsprung
• P pivot: sprung
• Materials: largely bronze, with steel parallelogram plates