Ever noticed how cars and motorbikes have smaller brakes on the rear...?
This is why dual-pivot brakes on the rear of road bikes are silly. Single-pivot brakes are perfect for the back, being lighter and having less leverage, meaning it's easier to avoid skidding and control exactly.
With cantis, you can alter the geometry of the straddle cable to achieve the same effect. It sounds like your rear straddle cable is set too low, giving the brake way too much power.
Originally Posted by
FBinNY
When I lived and commuted in Manhattan, I got so good at this that in an emergency stop (like behind a taxi cab) I could lock the front wheel, lifting the rear wheel, swing a leg over the handle bar, and step off the bike catching it behind me with my right hand. It looked spectacular when done perfectly, but I've also landed on a few trunks in my life.
Awesome. I'd love to see some vid of someone pulling that move.
The only thing I can suggest is to practice hard braking, until you can feel the point at which a flip is about to start, then ease off the front brake enough to prevent it. Do this at low speed and work your way up to the critical point by degrees, so you don't injure yourself learning to prevent injury. (the Catch-22 of learning good bike handling). It's important that good brake modulation is drilled so that it's totally automatic because you don't have time to thing about it during a 3 millisecond emergency.
When I first got a DP on the front, my first emergency stop sent me over the bars.
The next, my back wheel stayed in the air for a few metres, no problem. It was automatic once I realised I had as much braking as I wanted... can't do endos like that at will, though. Like I said, automatic...