Go outside .. take off front sprocket cover and count the teeth (write it down)
do same for rear sprocket..
Take that info and goto this site:
http://www.gearingcommander.com/
Load the stock for your bike (should be Kawi>ninja>250 08-12)
It will load stock gearing, which shows you speeds@rpms below
Compare that to what is on your bike...
I bet you see why your doing 80@xxx rpms