Brizzell said he suffered bruising on his neck and jaw, a sore neck, and grazes on his ankle and arm.
He contacted police and they appealed for anyone who knew the rider in the yellow and black lycra from the video to come forward.
A judge today described Dalton's actions as "silly and idiotic'', and convicted and fined him.
Dalton, from Queenstown who came to Christchurch post-earthquakes to work in the red zone as a project manager, shook his head as he left the dock.
Outside Christchurch District Court, he refused to comment.
The case had been adjourned so Dalton and his victim could take part in a restorative justice conference.
But defence counsel Jonathan Eaton today said while his client was "keen'', the victim was not.
He said that Dalton, a former mountainbike bike national champ, had gone up the Port Hills that day to escape work and family pressures.
But he snapped when the younger, faster rider was "on his tail'' all the way down and then told him he was "rude'' for not giving way.
"His view was, 'If you're good enough to pass, pass me','' Mr Eaton said.
Dalton had undergone anger management counselling, Mr Eaton said, adding he had submitted a letter to the court today from a mountainbike expert that addressed codes of conduct for trail riding.
Mr Eaton said the fact that the incident was captured on film had blown it out of proportion, leading to much "humiliation and shame'' for Dalton.
"It was a minor tiff on a mountainbike track where both sides are at fault,'' he said.
He was at a loss to explain why it became national news.
The lawyer warned that people going about recording incidents on cameras can inflame situations, and could lead to more assaults because of their "provocative'' nature.
Judge Smith accepted that the "viral'' footage seemed "quite disproportionate'' to what happened, but did raise concerns over the assault - especially given that Dalton pushed him twice, before putting his hand over Brizzell's mouth to silence him.
