Originally Posted by
neilfein
Sounds like the seatpost rack could work, but will the Dahon BioLogic postpump handle the sideways torque?
I don't know, but I know how to find out

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Another option... find a long and narrow rigid plastic box (like the ones they sell to hold CDs and DVDs) that fits on top of the Curve's luggage rack; attach it with velcro straps and mount your existing rack trunk on top of that plastic box. If it's wobbly, stabilize the whole thing with a strap or two up to the seat.