Sentinel1,
You may want to have a look on this thread:
https://www.bikeforums.net/commuting...rak-bikes.html
The guy (original poster) is looking for a bike for a train trip (not commuting, so thread might get moved to touring). He wants something sporty and light like a road bike. I posted that he may want to look at a Dahon Mu or Tern X series. You might want to chime in there. Please note, they guy doesn't want to spend for a new bike, but craigslist here has tons of Bike Fridays, Dahons, and Terns for sale used.
You may want to read my recent post, see if more info needs to be added. Thanks.