Police are investigating how and why the collision occurred, but revealed last night the truckie had the green light at the intersection.
"When I looked back I saw this [man] flying off [his] bike and at the same time the truck just kept on rolling over [him]," said Mr Maamaloa.
It was only when other motorists alerted the truck driver by tooting their horns that he stopped about 70m down the road.
Mr Maamaloa and four members of his family rushed to help but there was little they could do to save the dying man who is believed to have been in his late 20s or early 30s.
"[He] was badly hurt [but] still breathing and mumbling. We couldn't understand what [he] was trying to say. [He] died right in front of my eyes."
He said ambulance staff worked on the man, and tried to comfort him by rubbing his back.
A female tourist from a cruise ship at the harbour nearby was distraught after witnessing the collision, which happened about 2.15pm at the corner of Parnell Rise and Stanley St.
Police said it appeared the cyclist had been riding down Parnell Rise and was turning left into Stanley St when he collided with the truck, which was travelling straight through from The Strand.
Inspector Cornelius Klussein said the truck driver, who had the green light, did not know the cyclist had come under his wheels until being alerted by other motorists tooting their horns.
"He assumed that maybe something had come off the truck so he parked up to see what was going on. It was only when he got out that he saw that something had happened."
Barbara Cuthbert, chairwoman for Cycle Action Auckland, said the death was a tragedy.
"Cycling deaths with trucks are becoming a real worry. Quite honestly, it's just a horrendous accident because cyclists are so vulnerable when the scale between the truck and cyclist is so appallingly different. It's just not safe having the two modes sharing the same stretch of road."
Greens MP Julie Anne Genter said the city needed more dedicated cycle lanes, like other international cities.
"Cities like Auckland overseas, they're putting a lot more focus on cyclists. I think Auckland is falling behind. They [the authorities] have got to make it more of a priority.
"People feel really unsafe to cycle even short distances. There needs to be separated cycle lanes, particularly in the inner-city area."
In Auckland in 2012 there was one cyclist killed and 205 injured. Nationally there were eight killed and 828 injured. The numbers were similar for the previous four years.
The section of road where yesterday's accident happened, between Alten Rd and Tamaki Dr, is not considered a motorway, so cyclists are able to use it.
"There have been two serious injuries involving cyclists and four with minor injuries in the last five years [in that stretch]. And none at that particular intersection," NZ Transport Agency spokesman Ewart Barnsley said.
Richard Loseby, a cyclist who works near the crash scene, said the site was notorious for road users running the lights.
"I think it's because everyone is really amping to get through the lights and get on their way.
"If you're a cyclist anywhere between the port and Stanley St, you're in trouble. It's just continual trucks with heavy trailers going through. That would be Auckland's Bermuda Triangle, that's where the bad shit happens. I see it every day."
Road safety improvements between the port and Grafton Gully are being investigated by NZTA, Auckland Council and Auckland Transport. The issues to be investigated include plans for the safety of all road users and pedestrians.
