Why so many racers dangle their leg when they are braking a what could be the advantage? Psychological advantage? Weight transfer? Aerodynamic drag?
Legend says it makes you immortal and you can go faster enough to be the fastest in the corner. Just kidding. Let's take a closer look.
Motorcycles and tyres are constantly improving. So riders are constantly trying to find ways to get the most out of them. The braking with dangle leg is a great example of this. Technology has gotten to the point where the overload under maximum braking is so great that riders often slip their foot off the footpeg spontaneously. Valentino Rossi has figured out how to turn this inconvenience to his advantage. It didn't take long for other riders to copy this style.
2. You can make yourself more solid in the middle of the body. You feel more settled and stronger on the bike. You can use the outside footpeg more. You'll feel considerably more comfortable. Plus, you can rest the inside of your outer thigh against the tank more.
3. Last but not least, it's about aerodynamics. You want as much aerodynamic drag as possible when you're braking, like a parachute. The upper body goes over the plexi. The extended leg helps increase the air resistance. The air flowing over your body slightly reduces the load you have to hold in your arms. The extended leg increases the aerodynamic opening in the right place - at the bottom and on the inside. A bit like an air anchor.