Well is said Lycoming 360 engine in a Robinson?
I used to fly a R-22 standard in the US with a Mogas STC. It had the 320 150hp engine but I would think there would be an mogas STC for the newer engines also or not?
I did fly it some on Mogas and it made no difference whatsoever. These engines do not have that high compression that the octane rating will make any difference.