An issue has come up recently for people trying to get WOF’s – VTNZ insisting that the front brake must operate a rear brake light (as well as the rear brake operating the brake light).

Check section 4-10-2 to see the relevant section:

Mandatory and permitted equipment
1. A motorcycle first registered in New Zealand before 1 January 1978 may be fitted with one or two stop lamps.
2. A motorcycle first registered in New Zealand on or after 1 January 1978 must be fitted with one or two stop lamps.

This would seem to mean that you can just have one brake light, i.e.  operated by one brake.

NZTA WOF Manual

Lighting section of WOF Manual (PDF)