...I have no issue with a Rotax...
I don't either. I have 200 hours behind a fan cooled
SINGLE IGNITION 503 in a Tierra!
Low too! At 50' above the trees. The engine ran like a champ.
The 582 in the Mini-500 never gave a hint of a problem but you could tell it was being taxed right up to its max. Again, without problems.
I do consider myself pretty skilled at operating a 2-stroke properly and any 2-stroke in an aircraft, especially a helicopter, is NOT a crank-it-n-forget-it powerplant. They do require one of the following:
1) Run them slobbery rich, never letting their personality be shown, and accept the carbon buildup...
ORRRR
2) Lean 'em out, get 'em into the power band, and let them show off.
A 2-STROKE IS DESIGNED TO RUN BEST JUST ON THE EDGE OF MELTING. I was 100% comfortable running my 582 in the Mini with 1200 EGT's.
I was FINATICAL about my gauges being accurate on my EGT's and I watched them closely.
I think an aluminum piston starts to SMEAR like butter on the cylinder walls at about 1350. If I jetted the Mini for 1050, I could barely hover in cool weather.
It's a fine line.