Oil in wiring harness

Working on the electrical in my 1984 KZ1000P and found the inside of the harness extremely dirty and oily. Most everything seems to function. I’ve unraveled the loom under the seat to instal new fuse block and deal with constant on brake light (it was the front lever switch), and my hands literally were black when tracing the wires. Weird. Anyone seen this before? 

p.s. My wife suggested it’s the ghosts of uncaught traffic law violators… I don’t think that’s likely

If it is ghosts at least you know the bike will be fast if they were uncaught. 

Sure it's not degraded glue from the harness wrap? 

Yeah, I’m not sure it isn’t that. I just guessed at it being oil since it was so dark on my hands. 

Be sure to use non-adhesive harness wrap when you rewrap after cleanup.  Don't use electrical tape, it creates a sticky mess.

Check for leaks around the oil pressure switch. Mercedes have a huge problem with camshaft sensors leaking around the connector, I have seen them where oil capillary's all the way back to the engine ECU meaning a new ECU and engine loom (oh and a new sensor for $20  )