Mika Kallio will step back from racing to become a MotoGP test rider for KTM next season.
The Austrian company is entering the premier-class in 2017 and will now be helped in its preparations by the Finn, who raced in 'orange' from 2003-2008, winning 12 races in 125 and 250cc.
"KTM has played an important role in my career. When I first heard about their MotoGP 2017 plan, I realised that it might be a perfect chance for me to return to the Orange family," Kallio said.
"I am excited about our co-operation, since I respect KTM's know-how and way of working. I am eager to use my vast riding experience and analytic skills to do an excellent job as their test rider.
"My heart is set on this project and even though I will miss racing next year, I believe the best times are still ahead."
KTM Motorsport Director Pit Beirer added: “In addition to the technical and infrastructure challenges, the topic of personnel was no less important in the first stage of the project.
"By hiring Mika Kallio we now have our core team for MotoGP and are able to take the next steps. In accordance with our planning, the motor has been running on the test benches since the beginning of July.
"The next step will be the first roll out with Alex Hofmann, former Grand Prix rider and now commentator for MotoGP on Eurosport.”
Kallio, who has raced in all three grand prix classes, finished runner-up to Marc VDS team-mate Tito Rabat in last year's Moto2 championship. However he has endured a tough 2015, switching from Italtrans to QMMF during the season.