It's my firm opinion, and that of many people who've looked at it, that flipping over the bars is caused by the rider not bracing themselves as they use the very powerful front brakes.
If most cyclists don't use the front brake, that is their loss. Most advanced cyclists, in my experience, rely heavily on the more powerful front brake.
https://www.renehersecycles.com/how-to-brake-on-a-bicycle/ https://www.sheldonbrown.com/brakturn.html
If most cyclists don't use the front brake, that is their loss. Most advanced cyclists, in my experience, rely heavily on the more powerful front brake.