Absolutely no power, but battery is not dead

I have a 1982 KZ1000. The electrical system has been working fine until this evening when I took it for a ten mile ride. When I got back it sat for a few minutes. I then I went to fire it up again. When I hit the starter button the starter gave a cough and then the whole electrical system went dead. I checked the fuses, none were blown. I checked the battery and it is fine, putting out 12.4 volts. I've never had this happen before and I can't figure out what might be wrong. Nothing electrical is working. Completely dead, no lights, no starter, nada. Can anyone help point me in the right direction? I'm guessing a main wire failed, but I don't know where to start. I'm not super experienced with repair, but I understand the basics.
Thank you in advance!
Timothy

Fuses can look good and still be bad.
Steve

+1 on the fuse. Those old style glass tube fuses can be broken inside at one end or the other in a way you cannot see. One of the battery cables may have come loose. Check especially where the negative cable attaches to the engine or frame. Tight and clean are your friends. If all that checks out, a solder joint inide the ignition switch may have broken frm old age.

swest wrote: Fuses can look good and still be bad.
Steve

Your bike might have some spare fuses in holders inside the fuse box. If not, you will probably have to buy new fuses via mail order; finding AGX fuses (.25"x1.0") in stores is darn near impossible.

I took my 750 out for a run. Took some photo's of it and got back on. Dead as a donkey. Checked fuses. 2 out of the 3 had blown. got it started with the good one just to get home. Next day after replacing fuses. It happened again. This time it was the battery connections loose. It tried to start, then went dead. ( check connections are tight on both + & -. Might help in some way.

So, here's the update: I checked the fuses with a voltmeter and they are all fine. If I take out the 30amp fuse and put it back in the electrical system comes back to life. But then when I try to start the bike, the starter solenoid gives a click and everything shuts down again. I'm trying to figure out if the starter solenoid is dead or if something else is happening to short out the electrical system. Again, all circuits come back to life after I reset the 30amp fuse, but then everything shuts down when I hit the ignition switch. I get a click from the starter solenoid and then lights out. Any insight you guys can provide would be much appreciated!
Thanks,
Timothy

Did you clean the contacts on the fuse holders? Could be bad connectors too.
Steve

Steve, Yes I cleaned and checked the fuse holder, and no issues. It really seems like it has something to do with with the solenoid or farther down the line. Would the solenoid click if it's not working? I was reading that if it clicks it's working, so now I'm thinking something else is going on...
Thanks again for the help.
Timothy

If that 30a fuse is really any good, (ohm meter resistance can measure good while not under load) I think it is still the fuse holder or the way the wires are connected to the ends of the fuse holder clips.

Bruce,
I will recheck the fuse holder and the connections, but to me it seems like there's something else going on because the fuse is not blowing, but I lose power when hitting the ignition button. I pull the fuse out and the electrical system is back to normal.
Thanks,
Timothy

how would you recommend it be cleaned to ensure the best possible surface is available to the fuse? is handheld sand paper likely not enough to get through the oxidation?

I used chain saw sharpening stones. Got tired of that and went with blade style main fuse. Bad battery connections and ground wires can do that too.
Steve