just being a bit anal here - in reference to Yanis' statement "at least I got 75% power with sweet numbers" - if you think you're making 75% power because you looked at the power graph and looked up the power for a given RPM that is FALSE. that WHOLE power curve is at FULL THROTTLE. so unless you have loaded the engine with the prop to not exceed the RPM where 75% power is made you are NOT making 75% power. again, that WHOLE power curve is at FULL THROTTLE, as are ALL power curves for all engines. if you have the prop set to let the engine rev to the peak HP RPM (@ full throttle) and then throttle back to the RPM where 75% power is made (on the power curve chart) you ARE NOT making 75% power. you need to know the DENSITY ALT & RPM for fixed-pitch props and RPM & MANIFOLD PRESSURE & AIR TEMP for constant-speed props to figure out the actual HP @ that RPM & THROTTLE SETTING. the engine manufacturer publishes these charts. Rotax, as far as i know, does not supply a power chart for determining this.
