Event director Michael Davis said the response had been one of the best in the history of the event promoter Total Sport's portfolio.
"Total Sport have been blown away from the engagement and interest," he said.
"It's well over where we expected it to be, and has had incredible local buy in and interest."
With a slight differentiation to most multisport events, the bulk of the Wild Kiwi mountain bike leg takes place on the Jaggers' working dairy farm but he doesn't expect it to cause many delays or disruptions to milking.
"Potentially it could do, but we will plan around it. So any stock due to be in paddocks that [competitors] are due to go through ... we'll just have them out," he said.
"It will run between the course of milking so that won't have too much impact."
Outlining the key features, Jagger said "we think it's got a bit of everything in it", including plenty of opportunities for views of Bream Head and the surrounding oceanscape to be taken in.
"The thing with the course is that for the majority of people they like the scenery and views. So there are a number of points on the course to just stop and have a look. There's two or three, and one of them is the view they'll get when they look down Ocean Beach when they come out at the end."
In terms of difficulty, the course is not one for the faint-hearted.
After a short 300m climb over farm land, competitors will put the pedal to the metal on a speedy gravel road stretch. They will then cut through a farm gate and on to private farm land on a course which includes grassy farm land and gravely, dirt farm races.
About 20km into the leg, a two kilometre climb is set to test the limits of most, before a short, bone-shaking descent out on to the last farm section.
"It's not going to be an easy mountain bike course, it's going to be quite challenging," Jagger said.
"There's a couple of big hills, and one real monty.
"It's a zig zag track to the top and a zig zag down, so it's a pretty good hill.
"It's generally a good flowing course apart from a couple of hills. There's some fast bits and some undulating parts that will be a bit of work."
Taking part in the event himself, Jagger said the mountain bike leg is the least of his worries.
"I wouldn't mind a bit of wind. I'm doing the kayak leg for a team and would like it a bit choppy to slow these racing kayaks down a bit!"
For more information go to: http://thewildkiwi.co.nz/