Your USB adapter will be fine for anything that needs to be charged via a US cable. You're camera charger is another story. Like Komando said, you need an inverter to go from 12 volts DC that your bike supplies to 120 volts AC that your camera charger needs. The problem with this is the inverters are not real efficient, and if you plan on doing this on your XRL you're probably asking for charging problems. Not sure where you plan on staying at nights, but could you charge your camera battery at night say at a campground or a hotel? Maybe check to see if the camera manufacture has a car charger option for your camera that can plug into a 12 volt cigarette lighter outlet. The USB devices wont pull many amps and could be left on the battery even with the bike shut off for an hour or so, but an inverter or battery charger for the camera is going to run down the battery in a hurry. Don' leave power to it with the bike shut off.
84 Honda Goldwing (GL1200)