Tauranga Boys' College student Trent Haywood (14) died while competing in the Michael Godfrey MX Memorial in Omihi, near Waipara yesterday morning.
Police said the teen came off his bike on a 30m jump and suffered serious head injuries just before 11am.
Officers were unable to say what caused the crash; however, witnesses yesterday raised concerns about the size and shape of the jump, saying they thought it was dangerous.
About 100 spectators and racers, including Trent's father and friends, witnessed the crash. Paramedics revived the boy briefly at the scene before he died.
A friend of the Haywood family, who asked not to be identified, said Trent "had a lot of potential" and was on track to becoming a successful rider.
"He has been riding since he was just a little guy, about 4 or 5," he said.
"And he is just awesome, he loves it, motocross is his absolute passion.
"He has had a lot of success regionally and was starting to enjoy the rewards of hard work.
"This is just tragic. He was far too young but I can't help thinking he was doing what he loved and that is a lesson for all of us in life. Spend your time doing something you are passionate about."
Another friend of the family said Trent's personality and passion were "infectious".
"You couldn't help but smile when he was around and going on about motocross," she said.
"He was really positive, really fun and this is a huge tragedy for the family and his motocross family. We are all in shock. He is going to be sorely missed."
The event was cancelled after Trent died and the teen was later named a champion, coming first equal with another rider due to his points tally.
Nikki Shelley, secretary of Christchurch Offroad Motorcycle Club, which ran the event declined to comment yesterday "out of respect for the family".
The motocross community was yesterday in shock, with hundreds of people posting on Trent's Facebook page saying they could not believe he was gone.
"R.I.P bro still can't believe that you are gone. Such a good friend and had some good times with you. Ride in peace," one person wrote.
Videos of the talented young rider were shared, along with memories of his recent wins, including the recent MotoX in the Maize competition, where he took home the top competitive 250cc title.
The teen was also one of four taking part in the Team Moto City Bel-Ray Junior Development team and had several sponsors.
Sergeant Rob Irvine, of Kaiapoi police, said Trent's death was believed to be the first in the event's 35-year history.
The weather was fine and the track was largely dry, he said.
Police and health and safety officers are investigating.
