Very nice looking K75. Do you know what kind of seat it has? Looks like a low seat, but doesn't have that big rubber thing on the back of the tank.
Based on some of the problems I've seen others have, you might want to pull the starter apart and check the brushes along with cleaning the carbon dust out of the commutator. Another job to forestall electrical whack would be to go into the ignition switch and clean it out as well. These two items are responsible for a good share of strange electrical whack that can be very hard to diagnose.