I had old style 55w halogen spotlights, twin headlights and hotgrips on my Monolever 800 g/s and had no trouble with the stock system.
Everything was via relays to avoid leaving stuff switched on and also to avoid burning out the small switch contacts.
Mind you, I didn't ride about in daytime with my lights on, they bring for periods of darkness and reduced visibility.
I did, however, do a 300 mile night ride from Dover with the hotgrips on, twin headlights on, and occasional high beam with spots on, and had no trouble.