I have a Shindawa 23cc from a string trimmer. The engine is well made, has generous transfer port area and runs good. On Electronic ignition turns a Bambula 16 X 8 at 8200 rpm. It turns about the same on Glow/gas with glow plug, but the vibration is more than with EI. This is apparently due to a fairly high compression (effective) ratio and needs a higher octane rating fuel.