The ornamental design for a motorcyclestoragebox, as shown and described.
FIG. 1 is a perspective view from the front side of a motorcycle storage box.
FIG. 2 is a perspective view from the front side thereof.
FIG. 3 is a perspective view from the rear side thereof.
FIG. 4 is a perspective view from the rear side thereof.
FIG. 5 is a front elevation view thereof.
FIG. 6 is a rear elevation view thereof.
FIG. 7 is a top plan view thereof.
FIG. 8 is a bottom plan view thereof.
FIG. 9 is a left side elevation view thereof.
FIG. 10 is a right side elevation view thereof; and,
FIG. 11 is a referential perspective view thereof with the lid opened.
The portion of the motorcycle storage box shown in broken lines is for the purpose of showing environmental structure only and forms no part of the claimed design.