Hey Neil, running the exact same drive system as with the Dupor 196cc engine -jack shaft with fixed gear, single chain. It was a huge help that all the mounts, clutch and other parts fit the Honda GC160. Though had to do a different tank aranggement and exhaust. Seems to be getting the same top speed on a smoother running and lighter engine. Of course there are no mods for this engine - have to run stock other than the Mikuni carb added. Looking forward to chasing Scotto on his 99cc Preditor.
One chain with that jack shaft, are you running a geared hub? It doesn't look like it.