Carlyle sent around an email to his workmates a few months ago to see who would be keen to take on The Pioneer.
"I pitched it to everyone and said we will do it as a company ... I've done Ironman a few times and thought this could be something really epic."
Wyatt jumped at the idea while triathlete Harwood took a little longer to come on board.
The Pioneer is a new concept in New Zealand but is based on similar events overseas such as the Cape Epic (South Africa) and Swiss Epic (Switzerland).
Carlyle said, going off reports from those events, the most challenging part would be backing up each day.
"If you read the reports from the Swiss Epic, a six-day mountain bike event, you wake up each morning and you are sore then you complain for 15 minutes and you feel great. Then you get really sore again and do it all again the next day."
Harwood said many of their workmates thought they were crazy but it would be an event of a lifetime.
Remarkably, Harwood was knocked off her bike while training for a cycling event two years ago and was put into an induced coma.
She has made a great recovery and has continued to compete in cycling and triathlon events, quite literally getting back on her bike.
Competitors in The Pioneer must travel in teams of two and the event is limited to 250 teams. Three of Carlyle's good friends, Stephanie Miller and David Miller (US) and Ben Eitelberg (Auckland), will be joining them to make up three teams of two.
Wyatt and Carlyle will ride together while Harwood will pair up with Stephanie.
Harwood said they were all well into training and she would be doing the Ironman 70.3 Taupo in December to help her prepare.
Mountain bike enthusiast Wyatt suffered a broken collar bone earlier this year but has not pulled out of The Pioneer.
"I broke my collar bone at the end of August - a day before we were going to have a group training session," he said. "It crossed my mind to pull out a couple of times but you have to keep going."
Commonwealth Games gold medallist Anton Cooper is among the entrants taking part in the event next year.