The teenager died at the scene of the crash in Moerewa in Northland just before 1am yesterday.
Inspector Willie Taylor said it wasn't known why the boy was riding in the early hours of the morning.
A motorcyclist killed in the Bay of Plenty on Saturday night crashed after being told not to drive after drinking alcohol, police said.
Whakatane Police's serious crash unit were investigating the accident on State Highway 2, near Kutarere in the Eastern Bay of Plenty, in which the 25-year-old rider was killed.
The rider, who was not wearing a helmet, failed to negotiate a sweeping right-hand bend before colliding with a barrier and suffering fatal injuries.
Meanwhile, an Australian woman remains in a critical condition in Auckland Hospital after a quad-bike accident only days after her arrival in New Zealand.
Chelsea Callaghan, 38, of Melbourne, crashed during a farm tour at Te Kohanga, between Tuakau and Port Waikato, on Thursday afternoon.
Ms Callaghan, who was wearing a helmet, suffered a serious head injury and was in an induced coma.