Welcome to the site Jeremy, great to have you on board!
I have the same bike, so this will be an easy one to answer.
As Byte mentioned, the bike will tell you when it's labouring, but one advantage to our bikes is the torque they generate down low in the rev range.
Where some of the other bikes will need to drop back a gear, our can power out of it. Admittedly, it's not a perfect solution, but if you're lazy, it's workable!
I normally see myself in 6th on the highways running at about 4.5-5k revs @ around 110kph(So glad to talk with someone who works with the correct terminology!!)
What are you calling a long ride? 100-200kms? Just so you have a goal to work towards, I rode 1,119kms in 16hrs a couple of years ago, and looking to do it again when my summer rolls around.
Enjoy the ride, and let me know if you have any further questions.