Thanks for the nice flash-back Jock !!
Just a comment about the Ariel vs the Honda's sounds: Ariel being a two strokes engine has a power stroke every 360° of crankshaft rotation, both pistons being at the same angular position, we got two explosions at the same time. If I'm not wrong, the Honda was a four strokes engine, this combined with the 180° pistons offset gave the 1,2, pause sound. Would the Honda been a two strokes engine its sound would have been an even 1,2,1,2,1,2 at double the frequency of the Ariel ... (one explosion every 180°).
I can't see any advantage of the Ariel setup: a "180°" two strokes-two cylinders engine is nicely balanced with one piston in power stroke helping the other @ compression stroke, and vice versa, while the Ariel's 360° (or 0°) has to use the inertia to compress the mixture... and shake the all thing !
The only thing I can think of is the simplier crankshaft machining and therefore cost ...
Best regards, Bernard.