Dave ... I think our shared interests go back a few years. Here is what first inspired my curiousity about modifications and engine design. My first motorcycle, a 250cc Ducati Mach1 and Gordon Jennings; the Technical Editor of Cycle World.
http://www.eurospares.com/ducr2a.jpg
http://www.eurospares.com/ducr2b.jpg
http://www.eurospares.com/ducr2c.jpg
http://www.eurospares.com/ducr2d.jpg
I really loved that bike ... a colourful "Sprite"
EDIT - I should say I only rode on the street. My brother was the racer. To stay on topic ... these links highlight head modifications for the Ducati 250.
Keith raced a highly modified 250cc YamahaTD1A. A very talented engineer and rider. Quite proud of him.
