There must be ships leaving the East Coast that are destined to reach NZ. (though it would take longer, but not much if the Panama canal is being used) I'm sure a local shipping company could help.
As you will have permanent residency there may be a GST exemption that applies. You may want to check into that. I seem to recall something about it when I was looking at this stuff for Pete R.
But then of course, as it sounds like you will be here for the long term, or have permanent residency anyway, ordering what you want from here may not be such a big deal, though if you can get that trade in, avoid any US import or other taxes by re-exporting, and get a GST exemption, it would be one cheap bike.
