Hi Chuck,
I've never owned a Hirth. Do the problems extend throughout the Hirth line?
Jim
I would say the biggest problem is service. The factory rep is in Tiffin Ohio. Which if you have a problem you need to send the engine there. With Rotax I have 3 service reps within an hour drive of me.
I had the F30 engine. Never really seemed to run right. Even had 2 of Their service people from Germany who were in for Oshkosh try to get it running right.
I would say it had enough power for my 2 place but lacked enough torque to pre-rotate my 29' blades. Had to really speed the engine up so it would not die. Unfortunately with the computer for the engine all I could change was the idle setting. Any other settings/changes had to be done by the factory rep.
On the original forum there were various complaints about the other Hirth engine models.