Haumoana firefighter Senior Station Officer Graham Arthur said the man was conscious and walking when emergency services arrived at the scene.
"He didn't have any shoes that could be seen and definitely no helmet," he said.
"He had a few lacerations but our concern was head injury."
Head injuries were common when people came off motorbikes, Mr Arthur said, although the man did not appear to have any.
"He clipped the gatepost going in and that's what tipped him off, otherwise he probably would have slowed down before he hit anything."
The man had borrowed the motorcycle from a friend.
"It's the old story."
Mr Adamson said wearing a helmet was "absolutely basic" for road safety.
"If you come off a bike at any type of speed you can suffer significant head injuries that will potentially have a lifetime of consequences."
