I have a Rotax 912 ULS on a 2008 Flight Design CTLS. My mechanic did the annual in April, with 5 year hose change, new fuel pump and new rebuilt carburetor with the newer designed floats.
There has been issues with the fuel pressure and RPM every since the annual. On lift off and climb out I can get an additional 200 rpm by applying carb heat. After 20 minutes of flight, in level flight, without carb heat on I can see 5000 rpm with a lot of throttle movement left. I think something is unusual with the carbs or the air flow system since the annual. At taxi 1800 RPM the fuel pressure on the Dynon reads higher than normal - 5.7 to 6 PSI, yellow band to red line. At takeoff and cruise about 2.5 PSI, normal reading.
I am seeing 4800 RPM when applying full power on take-off out of a 6200" airport, normal, but starting the climb it drops to about 4600 RPM. I can't remember if it used to do that before the annual, or if I'm being super sensitive to problems. Your opinions please
