The ornamental design for a motorcycle, substantially as shown and described.
FIG. 1 is a perspective view of a specific, illustrative motorcycle according to the present invention;
FIG. 2 is a reverse perspective view of the motorcycle shown in FIG. 1;
FIG. 3 is a side view of the motorcycle shown in FIG. 1;
FIG. 4 is a plan view of the motorcycle illustrated in FIG. 1; and,
FIG. 5 is a side view showing only the frame of the motorcycle illustrated in FIG. 1, for clarity of illustration.
The portions shown in broken lines are provided to illustrate the intended environment of the present invention and form no part of the claimed design.