The 17-year-old German rode for KTM last year and joined Repsol Honda as team-mate to Britain's Bradley Smith and Esteve Rabat for 2007, but lost all interest in competition pre-season and quit the team before the first race in Qatar.
But his three subsequent wildcard appearances for Blusens Aprilia in Cataluyna, the Netherlands and Germany have included a career-best ninth place and re-kindled his drive for racing.
The son of multiple 250cc race-winner Helmut Bradl said: "I am delighted with the agreement, especially to be part of a German team.
Season 2008
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"We have spent a while discussing the possibility of this happening. I know I will feel very comfortable with the atmosphere and believe we can enjoy great success."
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Motorcycling
Rossi announces decision to retire at end of season
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