If you want to learn how to build a bike from scratch, buy a bike from Bikesdirect, they come fairly unassembled, then take it completely apart and put it back together. That'll learn you how to build up a bike.
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Il faut de l'audace, encore de l'audace, toujours de l'audace
1980 3Rensho-- 1975 Raleigh Sprite 3spd
1990s Raleigh M20 MTB--2007 Windsor Hour (track)
1988 Ducati 750 F1