James Hillier will ride for OMG Racing BMW at next year's North West 200 and Isle of Man TT.
Hillier, who was Man of the Meeting at this year's NW200, split with Bournemouth Kawasaki after a 10-year relationship with the brand.
The Hampshire rider grabbed his first NW200 success in the second Superstock race on the north coast in May.
OMG Racing, who will make their debut on the roads next year, have also signed Australian David Johnson.
This year's NW200 meeting saw the 34-year-old finish a close second to team-mate Glenn Irwin in the Superbike race and clinch third and fourth places in Supersport and Superstock races, in addition to his race victory.
Hillier has one Isle of Man TT win to his name after winning the Lightweight TT in 2013 and has 14 podium finishes at the event.
"I'm really looking forward to a new chapter in my career for 2020 with OMG Racing," said Hillier.
"I'll be working with a crew chief I know very closely and with the team to develop the bike. It's definitely the right time for me to make this move and I can't wait to get started."