Toprak Razgatlioglu will leave Yamaha when his contract expires at the end of 2023.
It is not known where the 2021 World Superbike champion, who has spent four seasons with the Japanese manufacturer, will go next.
Razgatlioglu said: "I want to say to the whole Yamaha family a very big thank you for the love and respect they have shown me.
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"To win the World Championship was my dream when I signed with Yamaha, and we reached that goal together.
"For next season, I feel I need a new challenge, and while there was an opportunity in MotoGP, I didn’t feel the same connection with the MotoGP bike that I have with the superbike.
"But if I am to stay in WorldSBK then I need a new target, a new ambition.
"I am sorry to leave Yamaha, both the brand and the people, as we have a very good relationship, but change is part of any sport and normal for any professional."
Razgatlioglu claimed the 2021 title to become Yamaha's first World Superbike champion since 2009.
Razgatlioglu made his superbikes debut in 2020. The Turkish rider won Race 1 at Phillip Island in his very first race.
He finished the 2020 campaign with two more wins at Circuito Estoril to end the campaign on a positive note.
In 2021, Razgatlioglu established himself as one of the best racers on the circuit, securing the title with 13 wins and 29 podiums.
He outlasted Kawasaki Racing Team's Jonathan Rea in a season-long title battle which prevented the Northern Irishman from achieving seven successive titles.
In 2022, Razgatlioglu produced more race victories, 14, than he did in his title-winning season but finished the campaign in second overall behind Aruba Racing–Ducati's Alvaro Bautista.
He also broke the record for the most wins for a Yamaha rider, surpassing the total held by Noriyuki Haga, who had 27 wins.

Bautista, Rea and Razgatlioglu – Defining crashes of World Superbikes 2022

In 2023, Radzagtlioglu has achieved 11 podiums from 12 races and one win at Mandalika in the Superpole race.
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