Debenham Sisters
Betty and Nancy Debenham, with their dog, Poncho, were keen motorcyclists. Nancy won a Gold Medal at Brooklands in 1926.
The Debenham Sisters
Picture of Butterworth's Swing Valve motor and now being installed in a featherbed frame.
The exhaust valve is conventional and the swing inlet (shaded)
Just swings out of the way! WOW! There are many advantages to this design.
See how many you can work out. Answers next month!
