Start Line Bug
The start line of the minimap is placed at the start position with respect to the position and horizontal rotation of KMP/KTPT.
But there is a Start Line Bug in Mario Kart Wii: For races in mirror mode, the rotation is not mirrored. So the start line has a wrong direction (same as unmirrored). Only if the horizontal start direction (y rotation) is a multiple of ±90° (one of 0°, ±90°, ±180° or ±270°), the mirror mode shows also a correct rotated start line because of symmetry reasons.