I've never had much luck with cigarette lighter plugs or adaptors on my bikes. Long ago, I changed over to simple two pole trailer plugs to power my GPS and other accessories.
It's a bit of a trick to get to an unswitched hot lead, and even more of a PITA to properly run a wire from the battery. I found an hot wire in the cowl, and cut and spliced in a fusible link. I ran a wire to the handlebar mounts, and then up the rear brake hose. The wires are under the plastic handlebar cover .
It's sort of a shame that Yamaha didn't install a 12v terminal from the factory.
Anyway, this is what I am using to power my GPS.