Er,
I can't help but notice that the engine in the pic is attached to the frame by what appears to be a set of leaf springs.
I take it that it's driving the wheel underneath through a reduction/clutch unit under the engine?
I presume that wheel is pneumatic? So that engine's just sort of jiggling there?
We all know where I'm heading with this.
Apart from the fact that it's air-cooled, what are the main differences between an LD1 and a CS? Less piston/flywheel mass? Higher speed?