Ductalk

Not only does a motorcycle’s fork compress under braking, as Nicky Hayden demonstrates here, it bends backwards, too. This can cause unpredictable handling.

Barring a few exceptions, the front wheel of your motorcycle is steered and suspended by a telescopic fork. Steering motion is a simple rotation around the steering axis, and suspension motion an equally simple sliding motion between two pairs of tubes.

That’s not to say that the forces and mechanisms involved are necessarily simple. Steering motion is constrained by steering geometry; by the forces generated from the rotation of the front tire, wheel and brakes; by the complex interactions of the tire against the pavement; and even by the rider’s hands in contact with the handlebar. To further complicate things, the steering motion can sometimes be damped by a hydraulic steering damper....more

Read more: http://www.motorcyclistonline.com/features/columns/122_1203_the_third_motion/index.html#ixzz1nPipjj2x