Some rpm numbers ....

APC 10x6 : 13.400 rpm
APC 11x6 : 11.900 rpm
APC 11x7 : 11.700 rpm
APC 12x6 : 10.700 rpm
APC 12.25x3.75 : 12.300 rpm

rpm numbers without muffler installed, after 1 hour break-in as user manual procedure, 95 IO fuel mixed @ 20:1 ratio (5%) Motul 800 full esther shyntetic 2 Stroke.

Engine needs more break-in time to develop the full potential .
Here is a picture of the piston ring after the first break-in session.
Sorry, but comments added are in spanish, but the picture talk itself



Best regards