burms

might sound a little stupid, but when i get really mad about not going fast enough around a corner 2nd gear or lower coming out of the turn(i know you asked about high speeds, but 2nd tapped doing a 180, i consider fast?!) i keep going faster and faster until i feel i am going too fast for myself. You know, getting squirrley and all (THE EDGE) if you cant find it, crash ,it hurts and hurts the bike, but you'll know how fast you can't go go close to that speed over and over, keep feeling the bike until you get the "sweet spot" you'll notice more traction in corners if you keep hitting it a little different until you get the most
as far as technique-try to be letting the cluth start to slip out before you even let off the rear brake-this too has its "sweet spot" as far as when to transition from brake to clutch (apex)and the correct tranfer technique

My Technique

I go like this...stay standing until right before the burm, sit down way up front with weight on the outside peg and inside leg straight out and held high, then as soon as I'm in the berm lean hard and get on the hammer. The inertia force from keeping on the hammer will keep you from falling inward. The faster you get the more you'll have to lean. The key is to get back on the hammer as soon as possible while leaning hard. Speed will get faster and faster.
Also, DON'T put your inside foot down if you feel yourself leaning in too much, get on the gas. This is a prime example of ACL injury.

Good luck and practice up.
Stan