“The trouble is you can print many items but the mechanical properties will be nothing like the original intent and strength.” - I have to disagree with you on that. There are actually good quality plastic filaments with extra strength characteristics like this Nylon Filament that can be used to create a full bicycle body. Take a look at this filament material from
3D2PRINT:
http://www.3d2print.net/shop/product/taulman618/.