The ornamental design for a bikelamp, as shown and described.
FIG. 1 is a front perspective view of a bike lamp showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a back view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top view thereof; and,
FIG. 7 is a bottom view thereof.
The broken line showing of the bezel, the button, locking guide, and USB port in the drawings shows subject matter that form no part of the claimed design.