Dave Walsh wrote on 9/16/2020 9:06 AM:
I can't think of anything polite to say about Wankel engines... a
vibration free engineers nightmare?

How is "vibration free" an "engineers nightmare"? It's certainly a pilots dream!
After 200 engine hours spread over 25 years, I have not had a significant
vibration induced problem! Try achieving that with a two stroke.

Here's some actual comparisons: a while ago, I searched the postings on the Wankel
powered Schleicher glider group for key words like "vibration", and also on the
DG/Solo group. There were few to found for the Wankel engine, and they were a
small minority of the issues discussed. The search of the DG/Solo group found a
LOT "vibration" issues, and they were the big majority problems.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1