Jonathan Rea says his decision to end his successful nine-year association with Kawasaki and sign a two-year deal with the Pata Yamaha team was motivated by the need for a new challenge.
Rea won six world titles in a row with his Kawasaki team between 2015 and 2020 but will move to the rival Japanese manufacturer for 2024 and 2025.
He said he pondered retirement before opting for the Yamaha move.
"I feel something new is going to reignite that flame again," said Rea.
Speaking to BBC Sport NI's Stephen Watson, he added: "It wasn't an easy decision but I just felt that I needed a new challenge."
The 36-year-old had one year remaining on his contract with the Kawasaki Racing Team, but that agreement was ended by "mutual consent". Rea will now partner Andrea Locatelli in Yamaha colours from next year.
The Northern Irishman will replace 2021 world champion Toprak Razgatlioglu, who is leaving Yamaha at the conclusion of the season to join BMW.
Rea lies third in the current world championship standings, a hefty 177 points behind Ducati-mounted Spaniard Alvaro Bautista, who looks set to repeat his 2022 title success, and 120 adrift of Razgatlioglu.
"It's something that has been brewing for a while and I just started to think, 'what's next?' after nine years with Kawasaki.
"I started to ponder retirement, what that would look like, and I didn't like that.
"There was an opportunity to do something new after Toprak left to sign for another team and it was something that lit the fire.
"I'm excited by my new challenge but not as much as I am to finish the year strongly with Kawasaki.
"The last three or four races have been very strong for us, we have been very competitive, so I'm looking forward to doing a really good job for them."
The most successful rider in the history of World Superbikes, the County Antrim man has racked up a remarkable 119 career race wins and 259 podiums in the 404 races he has competed in to date.
Fifteen of those successes came during the period in which he was part of the Honda team between 2009 and 2014, with the remainder secured during his record-breaking partnership with Kawasaki since 2015.
"The decision wasn't easy. These people [the Kawasaki team members] are my family, You travel together all over the world for nine years, hang out with them.
"What we've achieved together, we've broken all records, won six world titles on the bounce, and I have to thank them immensely for the opportunity they gave me.
"My childhood dream was to be a world champion and Kawasaki were the people who gave me the opportunity to realise that dream, they supported me all the way.
"It's something I know is best for me and I'm really excited about it.
"I'd just lost something. I remember how ruthless and competitive I would be in the early days, that was starting to wane.
"I was starting to accept my position and I don't want that. I want to be competitive, to fight for victories."
"Now is the time I need to trust in myself and do something quite new.
"But that relationship with Kawasaki will go down in history. You can't just close a chapter, that chapter will live on forever."
'A crying shame to walk away'
Rea admits that retirement was "a real option" which he considered after finishing third in the series in both of the last two years, and then struggling to contend with the leading two riders in the early part of this year's championship, largely due to a deficit in straight-line speed.
"I spoke to my family and the closest people around me [about possible retirement]," explained Rea.
"I'm still one of, or the best rider in the world right now, and to walk away from that would be a crying shame, just because things aren't going right.
"Also, I enjoy what I do too much and I don't have a 'Plan B', nothing lined up in the future that I'll walk into that will give me the same rewards or satisfaction as podiums and race wins in the world championship.
"Now I've got another opportunity with a successful manufacturer to do well in the future, keep challenging myself and see where it takes me.
"It's a lot of airports, empty hotels, time away from your family, so you have to be fulfilled for doing that sacrifice.
"At the minute I can't see retirement. I don't know if this is my last contract, you never know. I want to win and as long as there is that potential we'll keep fighting. I keep striving for perfection."
Having stood on the podium in each of the last six races he has competed in, Rea is determined to finish his final campaign with Kawasaki strongly.
"We've got three races to finish the season, the next two are back-to-back in Aragon and Portimao, two really good circuits for me, and I'd love to get another race win before the end of the year. That would be the icing on the cake, a present to my team really."
"I remain committed to fighting tooth and nail to the very last lap of the season in Jerez."