It was on relatively flat straight and empty highway all the times I went that fast. The first time was on a friends ZX-12R a hair over 170 to be exact. I had a Suzuki 1200 Bandit at the time (tuned-down, more upright GSX-R) which my buddy was riding and it was far from slow but the Ninja ate its breakfast easily.
Almost exactly like this one:
Crazy thing is that tucked in behind the fairing you have no idea how fast you are moving until well after you've surpassed ludicrous-speed on a full-fairing big Japanese sport-bike. The only other times I've felt eyeball-flattening acceleration like that have been taking off in airliners.
And that's a 2015 bike nosing out the F16 and full-on F1 race car. To be fair add a bit to the race and both the F1 car and the Jet (obviously) would outrun the H2R.
Results against that Veyron and the other "Supercars" however were laughable.