I used to test top speed of all my cars and motorcycles; not anymore with the fines and basically loosing your driver licence over 160.
This being said I did push the FJR to 240, the HP2S to 230 (the pressure on the helmet was unbearable) and one of the S70 also to 240. My Celica Turbo too. All indicated, so you can probably take off 10-20km to this.
Used to be able to have a good stretch of highway to oneself, but that never happen anymore, except maybe at the beginning of the pandemic but traffic is already back to normal, or close to.