Hi Elbot,

I admire your goal... and I eagerly anticipate the day when it is in fact a
reasonable option to print bicycles on home 3D printers. That's gonna be
awesome. Right now, though, with the Replicator as your primary tool, it's
a real challenge. Your difficulties will go far beyond your need to have a
one way ball bearing.

Should you choose to accept this challenge - and it could be a really great
project if you do - I think it will be best if you take this opportunity to
grab one of the CAD packages out there and learn to drive it. You clearly
have a lot of exciting ideas, neat images in your head. Your personal CAD
proficiency will always either limit or empower your 3D printing efforts,
at least until you're able to hire someone to do your design work for you.

Once you've gotten started working in a CAD package, I'm sure this
community will do whatever we can to answer questions you come across, and
try to help you get that bike rolling - or whatever else you choose to
design.

Best of luck,

Adan