That was the trick Bones. A few searches with "AMF" and I was on it...thanks! Here you go...
It looks like it’s an
Aermacchi Prototype and was never produced. The above photo and ones below were taken by
Eddie Boomhower at the Milan World Trade Show in 1975.

http://www.aermacchi-world.de/xr-250.html (the most uninformative spec sheet you'll ever see)
Tracked Eddie Boomhower to a website called Eddie Boomhower’s Race Reunion:
According to the website, Eddie Boomhower has been a friend of flat trackers before most of us were born. Not only was he one of the most successful Harley Davidson dealers in the USA, Eddie was also a race team sponsor and a race promoter.
Tracked the original photo in the first post to Eddie’s Picasa web-album, which has some other cool photos. Here's that link:
http://picasaweb.google.com/geoireland/EddieBoomhowerPics?authkey=Gv1sRgCObry_2NqK-t9gE&feat=directlink#Pheew!
