"It's probably going to take five-and-a-half to six months to do the whole thing," Mr Tracey said.
"North to South [Islands, in New Zealand], Perth to Sydney, Alaska to New York, around Ireland and then back home to Scotland."
The trip, which involves four flights in total, combines Mr Tracey's passion for cycling and travelling.
"I've been travelling for about 11 years now. The older I get, the more I want to try experiences that a normal person wouldn't do," he said.
"I love cycling, getting out on the road, getting away from the city life.
"I'm going to see Niagara Falls, New York, I'm going to see Alaska and the Outback in Australia. I don't have to pay for buses or taxis or trains or anything like that. I get to do it on my own bike.
"Once the visa's up next April, I thought rather than flying home, why don't I just cycle instead."
The cycling trip is also a way to raise awareness of mental health illness, he said.
"Two people every day in Scotland commit suicide. I think it's quite a big issue. This charity gives a lot of support to people in need.
"Everyone is connected to mental health in one way or another."
Training for the cycling trip involves a 30km ride on weekdays and a ride of about 100km on Saturdays and Sundays.
"But for Christmas and New Year I will be leaving Auckland. I'll cycle out to the Coromandel and I'll spend about a week and a half there.
"I'll do a 10-day tour. In that time, I'll be able to do more than 100km a day because the roads are ... longer and there's not as much traffic there," Mr Tracey said.
One of his sponsors, Evolution Cycles, had given him a good deal on his bike and gear.
"Everything on this trip is ultralight. The bike bag is triangular and it fits inside the frame of the bike. The bike's about 9kg, and then all my stuff on top of that is about 6 or 7kg.
"Most long-distance cyclists put 20 to 25kg on the bike, so I'm taking 10kg off that straight away.
"It's not difficult when you're going flat or downhill," Mr Tracey said. "It's when you're going uphill that's a bit of a killer, but over time my fitness is going to improve."
The bike will be boxed for each of the flights he has to catch during his trip, he said.
For accommodation, he plans to stay with members of the cycling community who host travellers, or freedom-camp.
"I don't intend on spending any money on accommodation anywhere."
He may also be joined by other keen cyclists on parts of the journey.
The village of John O'Groats at the northeastern tip of Scotland is marked on his map as the end point.
Last year, Mr Tracey raised 500 ($1020) for the Scottish Association for Mental Health on a 1400km cycle trip across Thailand and Laos.
To donate or read more about the trip, visit cyclenztouk.com.
