Police have described the incident as a "crash" and are not seeking anyone in relation to the death.
Traffic was diverted between Fairfield Bridge and Boundary Rd on Victoria St until early afternoon while police carried out a scene investigation. The man's body was sent to Auckland for a post mortem examination.
Police have identified the man but had to contact his relatives in the South Island before naming him today.
Detective Senior Sergeant Karl Thornton of the Hamilton CIB said the post mortem examination should give an insight into what caused the death.
"What I can say right now is our preliminary inquiries suggest that there is no indication that anyone else was involved in the incident," Mr Thornton said.
Police are still appealing for witnesses or anyone who may have information.
Residents living near the site told the Herald they did not know about the accident until they woke to find a crime investigation taking place outside their homes.