Just to add ...
The overspeed warning light is triggered by a device that fits in between the speedometer cable and speedometer, part number #12 in the diagram below.
The JDM K1 speedometer is a regular KM/H unit with one difference, the face plate which has red tick marks beginning at 80 KM/H and ending at 220 KM/H.
The overspeed light was originally equipped with a warning decal.
The Japanese market 750 parts book shows that K1 fork ears were painted in: candy blue green, candy ruby red, candy gold, candy garnett brown, valley green metallic and polynesian blue metallic. K1 fork ears were also available in unpainted/primer.