This is one of the main things that we all are keen on knowing..
The old Ninja 250 / ZZR 250 was got for around 105mph / 168kmh on the speedometer with a 5.75 sec 0-60mph (or 0-96km/h) :: Not bad at all!
Here are some video links of the old ZZR250/Ninja 250, notice in one of the videos, the bike goes to almost 170km/h!!