wassel

right I'm back from Saudi and finally got round to testing my wassell set ups on both the scooters. if I connect a h4 bulb across the 2 yellow wires from the stator it is bright at tickover and increases if I rev the scooters slightly.
once I connect the wassell I take a reading across the red and the black. the best I can get is 7 volts. this is the same for both scoots. I have tried it with a brand new wassell and it is the same. any ideas on why there isn't a 12 volt output from the red wire?
once I connect the wassell I take a reading across the red and the black. the best I can get is 7 volts. this is the same for both scoots. I have tried it with a brand new wassell and it is the same. any ideas on why there isn't a 12 volt output from the red wire?