You could also check out the Folding Bike Forum but I am currently using a folder for my commuter. I have it in my stable of bikes. I've carried it on Amtrak trains, Harlem North Line and Boston's Commuter Rail. All without a hitch. Mine is a da Hon Helios 8 speed. I'm 6'3, 185-195 lbs. so size wise it's pushed to it's limit. The little bike cooks along remarkably well. Just this past Sunday I did laps in Central Park and comfortably held with guys on road bikes going a good pace.