fixed
I own a 2012 yamaha with 200hp, its able to hit 70 on a flat lake, maybe a little chop, you wont go above 65 if theres many waves or other boats. You dont want to hit a wave going that fast bigger than a foot or two before it could throw you. Super dangerous, waters hard when its going 50mph, I know from experience. Ive been over 70, well supposedly hitting 75 but who knows how accurate the speedometer really is or if it was a current.
The reason they went for big 4 stroke motors is because reliability and easy maintenance, not to mention you dont have to worry about mixing a 2 strokes gas. The machines are larger to accommodate more people, and/or towing tubes, handle bigger waves, and are much better at sharp turns.