Help please. 1975 CB400F. My main fuse gets very hot when I have my headlight on. Bike is stock except for Dyna ignition. I unplugged the voltage regulator, rectifier, coils, starter relay wires, and all fuses except main and headlight. When I unplug the headlight bulb the circuit is OK. Bike running or not, same problem. Battery is not overcharging. Unplugged ignition switch and jumpered black an red wires according to schematic, no change. What to check? Fuse doesn't blow. Bike runs fine. Harness looks fine. Wires to headlight stay cool. I found the problem by just touching the wire while the bike was running. I have no idea how long I have had the problem. Any Ideas???
