Concur,, powder coat is not conductive, and hard enough to prevent the star washers from .asking it to grouns.. iirc, each instrument has it's own ground, so any ground surfaces need to be bare metal, to insure a good ground... if grounds are not done as need be,, you will have all sorts of gremlins...
Also, iirc, the. Faring grounds to the top tree, and the top tree grounds near the neck on the right side..
Lastly the powertrain has 2 grounds, one being the negative battery cable, and a second strap ground from a lower inner primary bolt directly to the frame..