Pressurized fluid motor comprising a casing, a cylinder block, a cam, an internal fluid distributor and a selector. The bore of the selector has four grooves. Two of them are communication grooves each connected to a main (feed or exhaust) power duct and to a connection duct, the connection ducts being themselves connected to different groups of distribution ducts. The other two grooves of the bore are branch grooves respectively connected to an additional (feed or exhaust) power duct and to a third connection duct. The slide of the selector comprises at least a first selection groove which is adapted to establish communication between the two branch grooves. By modifying only the shape of the slide, and possibly that of the bore of the additional duct, the selector can provide different functions.