Thanks for comments Dan and I take your point that early HD style cush drive couldn't affect stator - just armchair postulating on my part

.
As I've said before my personal view is that a cush drive be it between engine and transmision or within the rear wheel of shaft drive bikes cannot correctly be called a compensator as by (engineering) definition a counter-procedure is needed to
compensate. A balance shaft for example could therefore correctly be called a compensator as it fulfills that definition. It's just a case of semantics though and I'm feeling outnumbered so will put up and shut up
