1981 KZ650 wiring trouble

I recently tore apart a 1981 Kz650 Csr in order to paint and clean things up, I have most of the wiring back in place but have hit a road block. Im not sure if all of this wiring on the bike is stock, some things on the wiring diagram seem to be a bit different than what Im seeing on my bike. Coming from the positive terminal of the battery, there seems to be an extra wire that I cannot figure out where it hooks up to for the life of me. I've taken as many pictures as I can. When I turn the key, this seem to turn on except when I hit the starter button, nothing happens, not even a click.

that "extra wire" could be an auxillary port.. im not sure on these bikes but most i have worked on have some sort of 12v aux wire from the batter. :sick:

Some of the Kawasaki's have a clutch interlock, preventing starting the engine until the clutch lever is squeezed. To see if your's has one, look at the clutch lever, is there a small switch with two wires that go into the headlight housing? That's the interlock switch.

Do you have a wiring diagram? or factory manual?

There should be 2 red/white wires from the battery pos (+) terminal .
One of them goes to the main fuse box (20A fuse), then on to the ignition switch.
The other one is for the small accessory fuse box ( 2 10A fuses & 2 accessory leads). Stock, one of the accessory leads terminates there behind the side cover (black/white wire), while the other one terminates inside the headlight bucket (blue/white wire).

Here are some photos I happen to have... they may not be that much help, though.
The solid red & green wires in the 1st pic are the pigtail leads for a battery charger (not stock).

Thanks for all the replies guys! I believe the "extra wire" is supposed to be connected to the main fuse box. For some reason the coloring of the wires is different than the wiring diagram I have which was throwing me off. I'm going to tackle this when I get home today. I also think I do not have all the connectors hooked up in the headlight assembly which may be causing me some problems as well. I'll update tonight when I fix the problem if I figure it out. Thanks again thought I appreciate all the help!

UPDATE: I finally figured it out! The extra wire did in fact go to the main fuse box, but as for engaging the starter, the previous owner bypassed the clutch interlock switch. When I looked at the clutch handle, there was a spot for the switch and wires, but no switch or wires to be found. I eventually found the 2 black wires under the tank that must have been disconnected when I removed the wiring harness. All is good now. Again thanks for all the replies, you've all helped alot!

Is the clutch lever switch gone? If so, I would reinstall it to avoid any unfortunate mishaps.

yes, the switch is missing. I connected the wires for now just to get it running, but I will most likely be purchasing a new clutch switch. Thanks for the heads up!