Need advice for complete rewire of bike


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I'm looking at the daunting task of completely rewiring my XS650 from scratch. The turn signals and hi beams don't work, and the headlight and tail light are powered via tap splices into random key power wires. The entire wiring system is electrical tape and chaos and I can't figure anything out.

I've always been pretty bad with vehicle wiring; it's my least favorite part of the hobby, so I'm not really sure how to create a new harness for a bike like this. I'd like working lights and turn signals, spark for the engine, and a battery that charges, ideally as simply and cheaply as practical. The bike has electronic ignition, and all the chopper wiring diagrams I've seen online seem to assume the older engines with points. Does anyone know of a good, complete, simple wiring diagram for an electronic ignition XS-650?



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I prefer to make my own harnesses, but I've got all the supplies, tools, etc.
For the money, it's really hard to beat a pre-made harness. Here's one for a XS650SG (1st yr TCI) for $90 and comes with a new fuse box:
I actually enjoyed building my own harness around the Moto Gadget M-Unit for my bike.
Never done any auto-electrics before; and it did seem daunting at first. But being methodical and taking the advise from the forum members made the job easier. Great satisfaction when you test everything out and it works! My bike was a very non-standard machine to start with; but now I know every inch of the loom.
I’m looking into this now as well. If you want to build a new custom harness, study the circuits for the charging system (stator, reg/rec) and ignition system (pickup coil, ignition coil, tci), and it will start to make more sense I think. Throw that together with an inline 20A fuse, key and kill switch and you can kick start your bike. Basically everything else is a fused circuit coming off a fuse box.

But yeah, most practical might be a new harness from Mikesxs.
There are differences between the '80 SG and G (SPII) model wiring, so make sure you get the harness that matches your model.
In the "Some electrical diagrams" I like #4. The main diagram shows a basic points and mechanical regulator and silicon rectifier. In the boxes are the later TCI and combo reg/rec. Upper right is the starter.
Íf you are using aftermarket ignition or reg/rec then just study how the diagram shows the stock parts and the install instructions that came with the new parts to get things hooked up.
You can scroll through the diagrams and find one that shows the parts you want to use and go from there.