Hi Mike,
I think that a rebuild every 30 hours is a bit of overkill. It’s possible to save some money by sticking closer to the Rotax recommended rebuild intervals without risking major damage. The Rotax manual suggests 50 hours between rebuilds. I asked Andy Seeseman (who’s a 200+ pounder) about this and he suggests a top-end at 20-25 hours and a complete rebuild at 45 hours.
Charles