Have you hooked a meter to it?
I'd say get into the schematics and first look for where the generated voltage is sent from the Stator.
Then, follow that line and look for a way to electrically isolate the Stator from the rest of the system. More than likely it will be the female side of a plug you can disconnect and stick your leads in. (giggity)
With the bike off, read resistance through the stator. If reads infinite or 0, bad stator. If it reads normal, do it again with the bike good and hot, you should see a SLIGHT decrease in resistance. If you see a huge drop, or a complete breakdown, stator bad.
If that checks out...
You'll want voltage output readings at both engine hot and engine cold.
Do this the safest way possible. my personal favorite is some .032 safety wire (lock wire) wrapped around the leads and jammed in the hot part, so I don't even have to touch the leads at all.
Check the book or call the stealership for these values. Or the best way, do these same checks on a known good one and compare yours to it.
If your stator is good, start checking wires. Inspect all of them for nicks, cuts, damage of any kind. Especially near connectors and high wear areas. (tight spots, near where the seat locks in, etc.)
Read wires, piece by piece so you can isolate. reading through the whole harness will get you jack **** and is normally how a dealership will get to sell you a new wiring harness.
Hope this bit of information helps.
Sorry if I'm completely wrong, haha.
