A rake includes a frame and at least one arm assembly attached to the frame via an arm member. The arm assembly includes a main beam coupled to the arm member. The main beam includes a first member pivotally attached to a second member, and the angle between the first and second members is adjustable. The arm assembly further includes a first rake wheel unit connected to the first member and a second rake wheel unit connected to the second member. The arm assembly attaches to the frame such that in a work position, the first and second rake wheel units are disposed substantially horizontally extended with respect to frame, and in a transport position, the first and second rake wheel units are disposed substantially vertically above the frame.