That looks like a dream trip. Enjoy it. Do some prep stuff before you start off.
Go through everything visually, like electrical connections, pipework and any rubber bits.
While you have that wheel off, may I suggest you change the wheel bearings and seals.
Change the timing belts too, and have a good look at the water pump while you have the radiator disconnected.
If there is any lateral or rotary play, give serious consideration to changing it. It is not a difficult job
You can get a new pump from Caltric for about $80. Check out the hoses and clamps too, they are cheap to replace before you start off.
Fill up with fresh coolant. Some of the places you will visit will test your cooling system.
Go through all the brakes, check you have no leaks, good brake pads, make sure all calipers function and release properly, and change the fluid.
Check out the stator connections and operation. Get a kit of emergency spares to carry, and a small toolkit.
If you can, do a couple of test rides before you set off proper, gives time for everything to settle in and hopefully any issues will reveal themselves.
Dont forget that the bike has been resting, they don't like that.
I have just returned from a trip to the USA and I thoroughly enjoyed it. A wonderful country, and wonderful people.
I know you will absolutely love it. May the gods keep you and Amanda safe.