does your have the all in one unit, where the kill switch and light switch are in the same box on the same side of the handle bars. or is your like my 85 where there is two seperate switches. kill switch on the left bar, light switch on the right bar? could be broken inside the box if its the all in one unit. if so take it apart and check it out. look at the connections, check where the metal peices of the switches rub against each other to make sure your making contact, or not making contact. kinda sounds like something broke inside.
1985 KXT 250 Tecate - kx cylinder, kx ignition, bassani headpipe, answer silencer, v-force reeds, 38mm airstyker carb, +2 franks swinger, raptor rear shock.
1996 YSF240 Blaster - maxxed out!!!
Life's journey is not to arrive at the grave safely in a well preserved body, but rather to skid in sideways, totally worn out, shouting "HOLY SH-T, what a ride!"