the live wont work as a supply to fuse box(glad you know the wire i was talking about in the answer to your previous question)...reason being it is a pulsed supply which creates the spark and it also wont produce enough current to power lights etc. try looking around the flywheel area of the bike there should be a few extra wires coming from the coils behind the flywheel, if you find them and have a voltmeter then start the bike up and put one lead on the wire and the other on a bare part of the frame or motor and check for voltage. if you do find then that can be taken to the fuse box. Generally most bikes have a lighting and a charging coil so you should really find two power sources besides the one going to the CDI or coil. The next obstacle would then be to fit a rectifier and voltage regulator if you want to fit a battery without this you could do yourself and the bike damage as the battery would overcharge. In answer to the question about the earth lead, the frame of the bike acts as a negative so it will run without it connected, it is advisable to reconnect it though, the more solid the connection the more reliable the power supply....
Rowland, September 2006
