There are some known electrical gremlins, the FAQ has the details however it would be worth checking the white block under the tank as well as unplugging the regulator / rectifier to make sure all the pins are clean. Using ACF50 on the connections of both of these would help dispel water and keep them clean and moisture free, but if you have the time and inclination going through all of the wiring loom connections, unplugging them and applying ACF50 wouldn't be a bad idea. ACF50 is better than WD40 for this as it will get rid of corrosion and help maintain the connections as well as displacing any moisture.
Somewhere to start at least.
Somewhere to start at least.