Found one hanging next to the rear brake switch. Has a round crimped terminal on the end of it. Looks to attach to crank case but can't find any obvious location

Bike runs fine and charges ok, but any extra electrical draw when at idle causes a slight change to the tone of the fuel pump. Touching earth against frame or engine makes no difference 

Ok so you have found a loose wire, but where does it come from? Best to find BOTH ends before you start attaching it, on some of the bikes I've had the PO has either chopped or moved wires, one even had the wrong loom on it FFS! Always follow wires to both ends, makes it easier. All else fails, coil it up and tidy it away with a cable tie and forget about it.

Also, it helps if you say HELLO in the new members section, just sayin!