A friend of mine has one of those trike thingies with a 80 HP Rotax donk (which I think is the common HP)? & he runs it it at a much higher power setting using around 15 lph, (that’s what he plans) at 60 kts, seems happy at higher revs, prop /wing combo must have a lot to do with it.
on a side note bend in one once many years ago, felt really strange, not for me😉