Hey Phil, you know I have actually driven a RO80
back in 1993.
They have the characteristic PP idle, the coolest thing though is how it "bucks" in gear at light load and the no clutch system on changing gear, you just put your hand on the knob (BDC style) and it "responds" lol (disengages the clutch) and lets you change gear.
The bloke who had it was one of my customers in my engineering job and he was a scientist who bought it from new and even had spare motors for it, I got to see the internals and the PP intakes were tiny tiny lol.
Interesting piece of history