We claim the ornamental design for a bicycle frame, as shown and described.
FIG. 1 is a front perspective view of a bicycle frame showing our new design.
FIG. 2 is a rear perspective view of the bicycle frame of FIG. 1.
FIG. 3 is a front view of the bicycle frame of FIG. 1.
FIG. 4 is a rear view of the bicycle frame of FIG. 1.
FIG. 5 is a left side view of the bicycle frame of FIG. 1.
FIG. 6 is a right side view of the bicycle frame of FIG. 1; and,
FIG. 7 is a top view of the bicycle frame of FIG. 1.
The present application is directed to the shape and contour of a bicycle frame. The portions of the article shown in broken lines form no part of the claimed design. The design sought to be protected is not visible in the bottom view, and therefore that view has been omitted.