I second KWD's recommendation of BikeFriday bikes. I have a Tikit folding bike. Its far more stable and durable than any other compact folder I've ridden and ha

I second KWD's recommendation of BikeFriday bikes. I have a Tikit folding bike. Its far more stable and durable than any other compact folder I've ridden and have taken it over curbs and through pot-holes without a problem. Basically the folding mechanism can't engage as long as there's weight on the peddles. You will have some flex in the frame, but less in my opinion than other folding bikes I've ridden. All the issues with a lower slung frame still apply. The killer features for me are: 1) I can fold it in about 5 seconds; 2) I can wheel it around while folded; 3) other than the frame it uses standard bike parts. http://www.youtube.com/watch?v=fQscBxx7wLE http://www.youtube.com/watch?v=fQscBxx7wLE http://www.memagazine.org/contents/current/features/origami/origami.html http://www.memagazine.org/contents/current/features/origami/... http://www.youtube.com/watch?v=_Ci6Muhedms http://www.youtube.com/watch?v=_Ci6Muhedms