Originally Posted by
50PlusCycling
I wouldn’t worry much about the brand of the derailleur, both the Dahon and the Altus derailleurs are perfectly adequate, unless you are someone who comes from a background of motorcycle riding, and shift your bicycle as often as you shift on a motorcycle. If you ride a lot of bikes, and use the gearing all the time, you would notice the difference in shifting performance between different levels of components, and likely choose a bike with higher-end components, or swap them onto your existing bike (drivetrain upgrades are not hard to do).
I shift my bikes a lot more than I used to shift motorcycles. Human legs, even strong ones, are really low torque engines.
My 12-year old Dahon has a SRAM derailleur. I shift it constantly and it still works perfectly. I can't say anything about the Dahon derailleurs, but the OP can swap it out later if he doesn't like it. It's not like decent derailleurs are all that expensive.
Pete, is the bike going to be used on a boat? I kept mine on a boat for some years but I found it too bulky (even on a 54' sailboat) -- the Jetstream has 20" wheels and doesn't fold all that well. I'm in the market for a Brompton to keep on the boat.