Electrical system from zero

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Alien

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Hello,

I have a 1981 XS400 SE type 4G5. I bought it last summer and fixed carbs and rear fork. Did a test drive, then i replaced some wires and put it on hold . Now im looking to finish it, but the electrical system is not working and i have removed all of the tags from the wires, with my dumb head. I've decided to do the rewireing from zero, but i have really no idea where to start.

I can only see recitifer, regulator, horn, 2 coils and the battery. There's also 1 wire coming from the motor, 1 from near the gear box and one from close the back brake pedal(I know that this one has to go straight to the batterys minus). Any ideas, please?
 
Thanks xschris, its a good place to start, yeah, but i dont want to open up the engine to see where those 3 wires lead to. Thought maybe anyone here could tell me.
and thank you for welcoming :D and here is a not so good picture of it
CAM00021.jpg
 
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The first two look to be safety relays and the last one is you flasher relay for the signals.
 
Thanks, might get a little annoying :D but another picture
CAM00027.jpg


its also dripping oil, whats up with that?

and this wire is going to batterys minus, why is the other end here?
CAM00028.jpg
 
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The first pic is the wires to the stator/field coils. And at the bottom that wire goes to the oil pressure switch warning light. Last pic, that is the ground wire to the motor.
 
The deal with electricity, is that it needs to go around, to come around. Like that switch next to the door, That one, That is AC current, for that to turn on the light, you flip the switch, send a current of power to the light, it will make a round trip back to the switch, unless the light bulb is dead.

Now our bike is DC, (except for the part where the white wires are connected to.(with one exception)) So to keep it to the light metaphor, The source of the power is the battery, it stores the power till that one time you might need it. So when you turn the key to the on position, your bikes tail light turns on. So the energy is in the battery, then when the key is turned to on position, the bike opens the wires for the battery current to run from the battery, to the key switch (Main switch) to flood the lines with power. The power hits the lights, and turns them on. to complete the circuit, that electron needs to get back to the battery. and any break on either side of the light to the ground, will keep your light from turning on. I assume that you heard its amps that kill, not volts. You look at the battery at the auto store, and they talk about the Cranking amps, and stuff like that, Those amps are what is turning on your lights. 60 wats over your head, on your bike 12 or so, To answer your question, that is there, so that the manufacture doesn't have to run a wire to the battery for every component, and then the starter, is the biggest sucker of amps, and that is attached to the engine, so it makes sense to put the negative return line near the starter, on the block. Its just like a car in that aspect.

Hope that answers your question. Welcome to the forum, Did I miss your Intro, if I did sorry, Nice intro!
 
Yeah, thanks :)

Yet another part need identifing, this wasn't attached when i got the bike, yet it still ran. Seems like starter solenoid? thats for electrical starter?
CAM00030.jpg
 
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yup, yes it is. The + from the battery to this one, and another line to the starter,

The manual would have answered these questions faster? We put the manual on the top 3 sticky's so that new people can find them. You do take good pics.
 

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