In the 1970s, before the "aero" fad, the word was "light," and bicycles went under the drill to remove every spare gram of weight.  This classic 1976 Hetchins "Keyhole" model is an excellent example, with the lightening approach being applied to virtually every part.  It's also an excellent example of a classic lugged frame--check out the gold plating!  For more Hetchins bikes:  www.hetchins.org 
  
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