Curious. I had the exact same behavior with my then new 2014 Touring.
I took it back to the dealer snidely, "I don't suppose I need to invoke the warranty here, do I?"
Got the bike back, and it was fine. Asked what they did, and while they were circumspect, I got the strong impression they had loaded a new ECU map.
Certainly two weeks out, I'd be taking that bike back with a quiet suggestion they fix it or refund it.
Hope you get it sorted soon, and this is the best place to be to be a Rocket owner; past, present, and future.
And if you would please, go to the forum "Introduce Yourself !!", and, well, you guessed it, introduce yourself.
We're all about the people here, and we'd like to know a bit about you.
We look forward to your participation.