Grant Cornelius' wife knew something was wrong.
Mr Cornelius was spraying thistles on his small farm at Dairy Flat, near Albany, on Monday when his bike toppled over on a slope, trapping and killing him.
The Department of Labour is investigating the accident.
Yesterday, the department said health and safety inspectors had this year started visiting farms around Auckland to check how quad bikes were being used.
The visits had resulted in 117 written warnings or improvement notices.
Mr Cornelius' daughter, Michelle Geater, said her mother Sarah found him after noticing he'd been away longer than normal.
"He'd been spraying the paddock and it took too long. You know exactly how long it takes to use up 100 litres of spray," she said.
Her parents moved to the 20ha farm four years ago when they built a bigger house after moving from the old farmhouse 500m away. They had been married for 31 years.
She said he developed the property and, "everywhere you look it's just him".
"He definitely left a cool legacy for all of us. We're at Mum's at the moment and I'm out looking out over the farm at the moment and everything reminds me of him."
The family had been bracing for bad news but Mr Cornelius' death was the last thing they expected.
"We're all really in shock to be honest. It was completely out of the blue. We have a very sick grandfather who's 93, and have been preparing ourselves for the last 12 months for him to go and we all thought it was him when Mum rang us."
Her mother said she and her siblings David, 31, and Nicky, 25, needed to come and see her and then told them the bad news. He had five grandchildren.
"He was amazing. He was the best dad and grandfather you could ask for. He was the most giving person I know [and] was something we can all hope to aspire to one day."
Mrs Geater said he never missed her eldest son's rugby matches - "he was there every weekend on the side of the footy field" - and the day before he died the family gathered for a Father's Day meal after he'd taken her son to the drag races.
"We had a family meal and hadn't had one in a long time ... It's quite uncanny how things like that happen."
Her father had a bad back and did as much as he could on the farm of sheep and highland cattle, but Mrs Cornelius played a big part as well.
"We loved him so much. He was an amazing person with a big heart. I imagine it will be a big funeral with a broad range of people. He touched so many people, sort of like a stepdad to everyone you know. Anyone who needed a father figure Dad was there for them.
Department of Labour Northland service manager Rod Gibbon said the farm visits were intended to reduce the number of serious quad bike accidents.
"The statistics say it all - on average 850 people are injured each year while riding quad bikes on farms and five die. We must bring this toll down."