What is typical on freeway

That big windshield, sidebags, and backrest offer a lot more wind resistance at 80 mph than that of a stock (naked) bike. That may be the reason you aren't feeling the same pep at high speeds as some other KZ650 owners (including me). You might try removing those accessories as a test and see how much difference it makes. Ed

The windsheild and sidebags do have an affect, but I just put them back on a couple weeks ago when it hit 35 degrees for my morning commute to work. Something about me and cold that don't mix.

Except for the missing tires and seat, this is pretty much how it has been when I have been riding it.