The braze-on shift bosses, cable guides, water bottle bosses, and rear der cable stop could have been added later, which would argue for earlier. The clamp cable routing on the bottom of the downtube certainly tends to make one think it is earlier than 78. I don't know when Colnago started using braze-on cable routing. Below is the last version of dating I found in one of Chuck Schmidt's posts. I don't know who to attribute the compilation. If the braze-ons are original, then I would narrow it to 77. Lou Deeter, Temporarily in Scottsdale, Arizona
================================ Colnago Frame Dating, Version VI ================================
1969 and earlier? 1969 -- Playing card decal graphics 1969 -- Fork crown (sand cast) with two holes in each side 1969 -- Fork tangs wide, no cutouts 1969 -- Club cutouts in all three lugs 1969 -- Bottom bracket shell with drilled holes in circular pattern ---- 1970 -- Fork crown (investment cast semi-sloping) with two holes in each side 1970 -- Club cutouts in all three lugs but club in lower head lug is now larger 1970 -- Bottom bracket shell with club cutout ---- 1971 -- Fork tangs narrow, no cutouts ---- 1972 -- Club/COLNAGO decal on head tube/seat tube (seat tube Worlds bands) and COLNAGO on down tube 1972 -- Fork crown with clubs in top and two holes in each side 1972 -- Fork tangs with two holes (sometimes three holes) ---- 1973 -- Wreath seat tube decal with two Worlds bands 1973 -- Fork crown with clubs on top but no holes in each side 1973 -- Water bottle braze-ons on downtube ---- 1974 -- Fork tangs with club cutouts 1974 -- Club cutout in lower head lug only 1974 -- Shifter braze-ons on down tube ---- 1975 -- Vertical COLNAGO seat tube decal with diagonal worlds stripes ---- 1976 -- Fork crown with COLNAGO added to clubs on top 1976 -- Short Campagnolo dropouts ---- 1977 -- Top tube cable guide braze-ons ---- 1978 -- Fork crown for recessed brake bolt with shallow triangles cut into back 1978 -- Brake bridge for recessed brake bolt 1978 -- Short COLNAGO drop-outs ---- 1980 -- Fluted seat stay caps engraved COLNAGO and straight seat stays, no longer biconical 1980 -- Brake bridge with cast square boss for recessed brake bolt ---- 1981 -- Chain stay bridge is small spool shape, no longer tube ---- 1982 -- Chain stays stamped COLNAGO on sides 1982 -- Cable routing on underside of bottom bracket ---- 1983 -- Aerodynamic fork crown
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