Clutch neutral wire? well that's the light green wire it runs to a diode comes out of the diode changes to yellow/green leading to the clutch switch and starter relay which give power to the switchs (clutch and nuetral switch) I think I would be looking at the wires leading to the clutch lever you may have a stuck microswitch or a chaffed wire. or a bad bulb socket on the Neutrl light.