Crankworx broadcasts its core competitions live on Crankworx.com, Pinkbike.com and the slopestyle events are all broadcast exclusively on Red Bull TV.
An economic benefit report for Crankworx 2016, that was released earlier this year, estimated the festival generated about $8 million for the Rotorua economy - a $4.2 million increase on last year's event.
The drew grew about 10,000 visitors to the city with about 15,000 people attending in total.
Mr Mutu said one of the reasons the event would last nine days was the return of the
Enduro World Series.
"That has a huge world following and we wanted to give it its own spot running on the first weekend.
"And rather than keeping it all at Skyline, we also have the opportunity to activate the whole of the city and the forest for more community-based events.
"We just want to get more people on bikes and give the average Joe the ability to ride alongside the pros."
He said his biggest concern for the new dates was the weather.
"But that's the one thing we have the least amount of control over.
"The reality is our town is pumping at the moment and there was a space in the shoulder season we needed to fit it into.
"Before that I don't think we could fit another 15,000 people into Rotorua during the height of summer."
Mr Mutu said early-bird ticket prices were a much better deal than this year and were on sale now.
"Multi-day pass ticket sales have just opened and this year's family pass is just $180, at the early-bird rates. Kids 5 to 14 years old are $40, and an adult can experience all nine days of the festival for just $60."
Crankworx general manager Darren Kinnaird said it was important to keep prices as affordable as possible for the fans.
"The Rotorua mountain bike community is so committed and so strong.
"It's the ideal place for us to watch the sport grow with so many children coming out to Kidsworx and whole families gathering to watch the events," he said.
Destination Rotorua general manager Oscar Nathan said there were added benefits to bringing Crankworx to Rotorua.
"They allow us to celebrate our destination, the hot springs and wellness, Maori culture and our lakes, and owning those spaces where we can, and that's what Crankworx does.
"A lot of effort and energy has gone into getting the event to where it is now. The extension to nine days is great, and there will be a broader trade component to this.
"The whole event is growing in popularity," he said.