Quote Originally Posted by alpinerabbit View Post
I just had a road bike technique clinic.

They told us use both with the same emphasis, and true, the front has 70% of the braking power while the back has 30%.
This can be compensated: In an emergency stop, to avoid going over, slide your butt behind the saddle. In the extreme, so far that you are completely behind your saddle. Really straigthen your arms, pushing yourself back from the drops.

Practice on a light decline (safety first, try a parking lot). Accelerate and come to a full stop. Start going faster and braking harder. Do it as fast and hard as you are comfortable. You can make your back wheel lock if you have the courage. I didn't.
Alpinerabbit gives you GREAT advice.

The front brake is your friend. Learn how to use it.

Why do people go flying over the handlebars? Because they never use their front brake, are afraid of it, then one day they HAVE to stop for some reason, so they jam the brakes. Their body and mind is not trained for that, they don't know how to react properly to the forces that are applied to them, and endo they go. Or maybe they'll just use the rear brake and fishtail as described above, endangering themselves but also whoever happens to be riding next to them.

Practice, practice, practice. When you use the front brake, shift your body weight to the back of the bike and know that your arms will have to absorb the shock. Eventually you would be able to use only your front brake, but it's still a good idea to use a combination of both.