Ich würde auch auf die 70iger Tippen. Zugführung über dem Tretlager, keine Gravur an der Sattelstange und der Bremssteg ohne Würfel.
Du hast recht, 1980 kam wohl gleichzeitig der Bremssteg mit dem eckigen Knubbel in der Mitte. Also nach 1978 und bis ca. 1980 und dort noch bevor die Gravur auf der Sattelstrebenanlegung kam. Sagen wir deshalb dann ganz einfach 1979 bis Anfang 1980.
Aber warum grenzt du es so "genau" ein? Hat die Gabelkrone damit zu tun?
Colnago Super Timeline... corrections or additions?
==========================
Colnago Super Frame Dating (12.18.2011)
==========================
1968 -- "Super" decal on chain stay
1968 -- Fork crown (sand cast) with two holes in the points at each side
1968 -- Fork tangs wide, no cutouts
1968 -- Club cutouts in all three lugs
1968 -- Bottom bracket shell with drilled holes (eight in circle plus one in center)
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1970 -- Fork crown (investment cast) semi-sloping, flat front and back with two holes in
the points at each side
1970 -- "Playing card" club decal graphics (inspired by 1970 Milano-San Remo victory)
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1971 -- Fork crown with clubs in top and two holes in each side
1971 -- Fork tangs narrow, no cutouts (or rarely no tangs)
1971 -- Club cutouts in all three lugs but club in lower head lug is now larger
1971 -- Hole in lower point of seat lug (last year)
1971 -- Bottom bracket shell with club cutout
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1972 -- Black Club/COLNAGO decal on head tube/seat tube (two seat tube Worlds bands) and
COLNAGO on down tube
1972 -- Fork tangs with two holes (or very rarely three holes tangs or no tangs)
1972 -- Derailleur cable guide braze-ons top of bottom bracket shell
1972 -- Water bottle braze-ons on downtube
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1973 -- Wreath seat tube decal with Worlds band at top and bottom
1973 -- Fork crown with clubs on top but no holes in each side
1973 -- Fork tangs with club cutouts (or rarely two hole tangs or no tangs)
1973 -- Club cutout in lower head lug only
1973 -- Introduction of the Super Pantografata
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1974 -- Shifter braze-ons on down tube (option before this)
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1975 -- Mexico model introduced
1975 -- Diagonal Worlds band added behind black Club/COLNAGO head tube decal
1975 -- Diagonal Worlds band with yellow Club/COLNAGO head tube decal used for one year
1975 -- Vertical COLNAGO seat tube decal with single diagonal Worlds band at top
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1976 -- Fork crown with COLNAGO added to clubs on top
1976 -- Short Campagnolo or COLNAGO dropouts
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1977 -- Fork crown with shallow triangles cut into back (no recessed brake bolt)
1977 -- Top tube brake cable guide braze-ons (an option before this)
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1978 -- Fork crown for recessed brake bolt with shallow triangles cut into back
1978 -- Brake bridge for recessed brake bolt
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1980 -- Fluted seat stay caps engraved COLNAGO and straight seat stays (no longer biconical shape)
1980 -- Brake bridge with cast square boss for recessed brake bolt
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1981 -- Chain stay bridge is small spool shape (no longer tube shape)
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1982 -- Chain stays stamped COLNAGO on sides
1982 -- Derailleur cable routing on underside of bottom bracket
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1983 -- Aerodynamic fork crown
http://www.bikeforums.net/classic-vintage/830017-colnago-super-timeline-corrections-additions.html