Whoops. I meant to say when exiting hard out of a corner, going downhill, and cresting. All of these conditions will upset your chassis a bit and greatly lighten the load on the forks and cause the wheel to caress the ground. Scary when it happens. Sometimes, your bike just doesn't have anything left to wheelie, lift, and recover once it starts. The only word of advice in that situation would be to sustain engine RPMs, try a very very slight weave to use the road as a damper. Slamming the brake could make it swerve, letting off the throttle as well. The softer more streetable forks are a little more prone to this because they have a more gradual gradient to which they dampen and rebound. A tank slapper on a true track bike is in God's hands, and a crafty rider-oh... and a sweet damper. Here's someone else's take on it... how you deal with it depends on you. I try not to ponder what the bike wants/needs as I ride it by doing complex calculations and recalling what I've read somewhere. I feel for it. That's all you need to do. http://www.ducatimonster.org/forums/riding-techniques/141145-head-shake-why-does-happen.html http://www.msgroup.org/tip.aspx?num=190