Recently started a new job and a moderate amount of travel is in my future. I have heard thatsome companies can convert old steel bikes into foldable ones that fit into a standard sized suitcase, or that some compaies build these new. Does anyone have any input on this? Anyone have one or had one converted?

P.S. I have no interest in the Dahons and foldalble bikes with the mini 20in wheels.

Quite a few of the custom builders will make frames with S&S couplers, which allow you to break the bike down for air travel. They also can modify existing steel frames. If you do a serch on this site you probably can find some pictures and discussions of bikes with this feature.

Richie offers a road frame called the "breakaway" that uses a different kind of mechanism but it's the same idea. Go to GVHbikes.com to see these.

I don't have either, but have heard positive things about both S&S and the Richie design. The couplers don't affect the ride or performance of the frame. Kind of a hassle to break down and set up from what I've heard, but they allow you to pack a conventional road bike for air travel.

S&S couplers allow you to use a "traditional" frame design.

Co-motion (http://www.co-motion.com) is one of the better known companies making new S&S coupled bikes. They seem to be highly respected.

S&S couplers are made by S and S Machine. Their website is:
http://www.sandsmachine.com/
There is a lot of good information on this site. Also a list of builders that build new and do the retrofits:
http://www.sandsmachine.com/fbplist.htm#USA

As the previous poster said, Ritchey came out with a different implementation: http://www.ritcheylogic.com/web/Ritchey~Logic/Ritchey~Site/web/EN/main/breakaway/20796.html#