TOPIC:

So I am going to relocate the ignition switch on my 1982 KZ750H. Want to go to a universal style that is much smaller. Like this one:

Going through the wiring diagram it seems pretty straight forward to change out except for one wire. You can see the six main wires and one out to the left that is brown that seems to provide power to the OEM switch. All the replacement universal ones I have seen for sale do not have this connection, merely the 6 main wires. If I go with an universal type can I leave the brown wire off and capped? I guess I am asking what does that brown wire actually do and do I need it for an universal style replacement?

There's a white wire from the 20A fuse which provides power to the ignition switch. or maybe white/black? The brown wire circuit supplies power to the horn & some other components, and it also acts as a voltage sensor for the regulator-rectifier. If the voltage from the brown wire is too low, the reg-rec senses it & charges the battery. Some new reg-recs have internal circuitry that senses the voltage, so those don't need to be connected to the brown wire circuit.

Edit: I'm not sure of the best way to install a universal ignition switch.

Edit: Unless I'm reading the diagram wrong, the brown wire also supplies voltage to the 10A fuses in the main fuse box.

Thanks, would it be possible to splice the brown into one of the other wires, like the grey one (possibly B/W not sure on my wiring diagram) that runs through the 20 amp fuse. I think that is the one you are talking about that supplies the power to the switch, if I am reading my diagram right (which I could very well not be)

What wiring diagram are you using & is it from the mbsween.bike-night site?
I think the diagram you provided is from an 80 or 81 model. 1982 = H3.

you may be right about it being the wrong one, not sure where I got that the diagram I used above from. I did look at the 82 H3 diagram in the filebase

1982 H3 Diagram KZrider

It has the exact same setup for the switch. From what I can read of the diagram it looks like if you start at the battery there is a red/white wire that is connected to a 20 amp fuse, which goes to a white wire, which in turn gets split to a black/white wire and a white wire, both of which go to the switch. So I was thinking if I tie in the brown wire to that white wire (before it gets split)? But not sure if that would put too much a strain on the white wire as it seems there is an awful lot tied in to that brown wire. (at least 3 lights, 2 switches, the horn , regulator)

If I try that route would it be a bad idea to add an in-line 20 amp fuse where I would split the white wire?

Again that is if I am reading the diagram correctly.... I obviously highlighted what I think is the path with yellow here

Something like this, Would it work to connect a section of wire (red in the badly drawn paint pic) from white to brown with a 20 amp (?) in line fuse between it

I think the problem doing it that way is that the brown wire circuit will be hot all the time. ???

Here's a topic with a bunch of wiring diagrams provided by loudhvx.
1980 750H bare bones for mattylight (pg 1)