speedframes

[karl shah-jenner <shahjen@xxxxxxxxxxxx>]

'a friend' just shattered his helmet and most of the frame faring when a few 
stone chips from oncoming vehicles hit his bike at speed.. yeah, this person 
was goofing around a bit too much.

http://members.iinet.net.au/~shahjen/speed.jpg is the image, and I'm curious 
whether anyone would be able to suggest a method of determining the exposure 
duration based on the speed and the (small!) amount of motion blur in the 
frame?