Hey it was not my intention to make it a pissing match...
The guy who started the thread wanted to know why Hirths aren't more popular in the gyro world, I was just sharing my opinion that part of why you don't see more of them is they have had a bad track record for reliability in my opinion.
I do not know every Hirth owner out there, but I do personally know of probably 20 or more Hirth owners and out of those only two claim to have not had some kind of malfunction. Everyone else has had some kind of issues with their engines, be it bad crankshafts and clutches ( Dave Seace ).... crankcase halves not aligning properly, spark plugs being blown out of the cylinder ( Mike Solano )..... Sparkplugs blowing out of the cylinder ( Tom Carslie ) .... Bad clutches, fuel injection system running to lean, fan bearings siezing, etc.... ( Maxie Wildes ) .... Broken cylinder, oil leaks, vibration induces cracking off of coil mounting plate ( Robert Klutz )..... Spark plug blowing out of cylinder, vibration causes coil mounting plate to break off engine ( Mike Bantum ) ..... Engine starts weaping coolant out of the side of the cylinderhead, engine vibration cracks off 4 studs that hold on waterpump, engine vibration causes one of 4 bolts that hold coolant manifold to rear cylinder to unscrew and cause loss of coolant in flight leading to overheat and forced landing, ( Barry Kroplien ) I could go on, but you get the point.
Sure Rotax owners have had failures too over the years, And not all Hirth owners are sure to have problems. But to me, there is certainly more risk flying Hirth than Rotax. Like I said last night, I would love to have a Hirth F-30 on my gyro, not because I think it is a great engine though, only because it is the only engine in that power and weight range that I think I could afford to buy.