The simple answer is, our game is 100% realistic when it comes to corner entry and exit speeds.
However, because in a video game you cannot feel the G forces of the bike, you will appear to be going much slower than you actually are.
In reality, during those slow moments the bike is in fact on the limit of grip capability and it would be impossible to accelerate any more without crashing.

We invite you to watch the video below for a more detailed explanation: