The Shimano Lark is a Skylark with the cable clamp bolt mounted on a sprung ‘cable saver’ arm. I have always liked this feature as it gives a pleasant supple feel to the gear change.

I think this example is the first version with the aluminium(?) nameplate and screw pulley cage stop.

• Derailleur brands: Shimano
• Categories: Shimano - from Skylark to world domination
• Country: Japan
• Date of introduction: 1967?
• Date of this example: 1967? (date code is 4M, ‘333’ marking on pulleys)
• Model no.: unknown
• Weight: 357g including hanger plate
• Maximum cog: 28 teeth
• Total capacity: 28 teeth
• Pulley centre to centre: 54mm
• Index compatibility: friction
• Chain width: 3/32”
• Logic: top normal
• B pivot: sprung
• P pivot: sprung
• Materials: steel