first of NEVER NEVER NEVER use brakes in a corner unless you absoluty have to unless you want to pick you and your bike up off the ground.(im not saying it cant be done but its not safe at all) alot has to due with body position, experience, and how comfortable you are with speed. I tend to accelerate all the way through the corners. A good trick to start with is look all the way through the turn about 30-40 yards ahead of you. If you are only looking 10-15 yards ahead you tend to have a bad line through the corner and have to correct your line.