A Surly Moonlander with a Bionx Electric Kit could help hauling that 50+ lB kit out of NYC.

http://www.youtube.com/watch?v=NY7UO9erG0I

A modified fat BOB trailer could also be used with the Surly fat bikes

http://www.youtube.com/watch?v=zX-TQQB7xTY

I would also check out coastkid71 Youtube page to see how those 40 somethings are still having fun on their mountain bikes.

http://www.youtube.com/user/coastkid71

i.e. Along with the dated Retro Music laugh

http://www.youtube.com/watch?v=kVpLZgzwqc4