The ornamental design for an electric bikeframe, as shown and described.
FIG. 1 is a front and right side perspective view of an electric bike frame embodying our new design;
FIG. 2 is a right side elevation view thereof;
FIG. 3 is a left side elevation view thereof;
FIG. 4 is a front elevation view thereof;
FIG. 5 is a rear elevation view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a front and right side perspective view thereof as part of a complete bike.
The broken lines in the drawings illustrate portions of the electric bike frame and environmental electric bike structures that form no part of the claimed design.