As long as you can ride +10% faster than the other traffic, your are fine!! 
I prefer to ride in the far(slow)right lane and travel at 100-110km/h(6800-7000rpm)for better fuel mileage(70+mpg)
Smaller roads?
I do not like highways when riding around for fun.
I have lots of good country roads with 50-55 mph signs (80-90kmh), some areas even a little bit less.
A few almost highway style, 100-120kmh for a short while or when in a hurry.
Cruising around in 80-100kmh (50-60+ mph) is nice and what I mostly do. Enjoy the views.
It happens I need to check the acceleration well beyond the signs for a limited distance. Keeping my eyes open for cars with blue flashlights means stress. Some of them have no visible flashlights until they are turned on.
Some roads have cameras. I avoid them even if the camera does not take a photo of my reg plate.
It was different in the 80's when I rode on highways all the way to Austria, Italy, Spain etc.
Below:
80 kmh road with nice bends. One of them has a good straight part for needle check, 100-160kmh.
There are others where main jets can be verified too.
But a wildlife fence is needed for higher speeds as many highways have.
Old ride photos. Early April 2021 and late October 2024.

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Needle check, cruising and slowly increase and decrease throttle.
