A motorcyclist has died at the Hampton Downs motor sport park in north Waikato.
The man was taking part in what is known as a ride day, where riders are able to take their own motorcycles to the track. The bikes are checked before they are used.
The man was testing the track when he lost control of the bike and it is thought he died instantly.
The track's chief executive, Jamie Kett, says staff have been left shaken.
He says the police and the Department of Labour are at the site and the track will complete its own review.