Bennett's friends rushed to the site after being told by those who had been following the star that there had been a crash.
The group left a petrol station on Quay St about 1pm. The plan was to ride through town over the Harbour Bridge to Albany and Riverhead, before ending the day at a bar in Ponsonby.
Friend Gareth Williams said: "[We] left Albany for the second half ride. Johnny and the group headed off and it was in this section Johnny had come off the road.
"From what myself and other riders there think, it could be due to the loose gravel on the road, which I believed caused the accident."
Williams said half the group, those ahead of Bennett, were unaware there had been a crash until they arrived in Riverhead.
"The ones behind Johnny didn't see how the accident happened due to the corner and being some distance behind.''
Williams said he and others arrived at the crash to find friends and family doing CPR on their friend.
He said they "did everything possible'' to help Bennett.
Paramedics arrived quickly after and more efforts were made to save his life.
Among the riders, shock started to set in, Williams said.
"Unfortunately, after the ambulance and other services arrived and worked on him, we had been informed he didn't pull through.''
A day after the crash, fans visited the site. Some left flowers, another left a bottle of Danger Lager, while others stood silently before leaving.
Online tributes continued also, from fans all around the country and overseas as well as from a number of New Zealand celebrities.
Williams, who met Bennett last year, paid tribute to a man who had a huge heart for others.
In particular, he had dreams to help raise funds for those affected by mental health issues and cancer.
"He discussed with us a few ideas, over the past months, of getting involved in raffling some things so he could give the profits to mental health and prostate cancer charities.''
Many of those taking part in Wednesday's ride are linked with Wolfpack Inc, an organisation set up to help raise funds for mental health charities, which Bennett was also linked to.
Williams said many of the riders were still in shock about losing a friend.
"Those who knew Johnny knew he loved riding and having a laugh. He was a solid bloke who loved a Danger Lager as long as it was backed up with the danger swig and a good party.
"He achieved huge things and had so much love and things to give back. He will be deeply missed and our thoughts and prayers are with his family and friends.''
Police are investigating the crash.
