He also worked hard to qualify for Sochi and was on the official long list of potential competitors, but was not selected for the final team of 15.
Last night, the New Zealand team paid tribute to Bagley from Sochi.
"Our thoughts and prayers are with the family and friends of Hamish at this sad time," chef de mission Pete Wardell said.
"He was a bright and talented young man who made a positive contribution to winter sport in New Zealand. He will be sorely missed."
The New Zealand contingent would gather this morning to acknowledge the snowboarder and the role he played in their close-knit community, Mr Wardell said.
Bagley competed in five events on the international circuit, most recently at the Cardrona skifield near his home town in August.
He was also a member of the Snow Sports New Zealand high-performance development team.
Snow Sports New Zealand chief Marty Toomey said staff and athletes were deeply saddened by the news.
"Hamish was a dedicated athlete with a promising future ahead of him," she said. "Any young life taken early is tragic and our condolences go out to the Bagley family and his friends."
Father Roy Bagley, who was making his way back to New Zealand from the United States, said it was too soon to talk.
Friends and fellow snowboarders paid tribute on Twitter.
"With a heavy heart I hear of a young life taken too soon. Rest in peace Hamish Bagley," wrote snowboarder Rebecca "Possum" Torr, who is competing in Sochi.
Snowboarder Brock Crouch tweeted: "We lost a great one last night. Rest in peace Hamish Bagley #Irideforhamishbagley."
McKenzie Raley said on Twitter: "You had so much more life to live.. Rest in Peace Hamish Bagley."
Bagley also appeared as a "Weet-Bix Kid" in a television advertisement for the cereal brand in 2010. In it, he was shown snowboarding and skateboarding as part of a group of teenagers.
Sergeant Derek Ealson, of the Cromwell police, said Bagley's Subaru Impreza apparently missed a corner north of the Cluden Hill summit on Sunday night.
The car crashed into a fence and tree before coming to rest about 30 metres below the road at the bottom of a steep bank.
The car exploded and burst into flames as a following motorist approached. Speed and alcohol did not appear to be factors in the crash, Mr Ealson said.
"The vehicle will be examined, but at the time the ... weather was fine, the road was dry, there was little traffic, so none of those factors have played a part."
