Well, just my words,,, but I hit the limiter in 3rd on the highway,,, and no, it doesn't hurt your bike, unless like the guy above said, mishifting,,,, however, I've noticed that if your that high in your RPM's usually your speeding up and not slowing down, therefore you should be shifting into the next gear around 13K Rpms, anything after that is really not gonna help speeding up, you can use those extra 1.5k RPMs (between 13K and 14.5K to up shift without letting off the throttle!