Os 50sx midrange

[xxxntwv]

I have an os 50sx.rebuilt with the hyper piston and sleeve.the engine runs good but is really rich in the mid range.idles good 4sec on the pinch test and seems good on the topend topend but when at a hover smokes excessively.do I adjust the needle valve to cure this or the mixture screw.its in a trex nitro pro and I fly without a governor.also what kind of flight times am I to expect.I'm only getting around 7:30 to 8 minutes in idle up doing mild 3d.

[mr_squiggle]

Mid range is controlled by the needle valve, but it does balance with the idle mix. You'll need to set the needle to be correct for your normal flying rpm, not necessarily max rpm. Depending on what your throttle curve looks like could mean more juggling of mix too.
Set the needle for best mix at max load.

[xxxntwv]

heres the issue I'm having,main needle tuned for max power,mixture needle tuned for good idle when I'm in a hover at approxamately 50% and carb opening the engine wants to load up to the point where it loses head speed and wants to quit if i stay there very long.I've leaned the main needle quite a bit and it doesnt seem to change the problem I'm having.so if i lean the mixture needle will the engine then not be too lean at an idle?

[DUCDOC]

I am having a similar problem with mine. I am at 1.5 turns on the needle and am afraid to lean it out too far. The governor is having issues maintaining RPM because of how rich the setting is. What are peoples needle setting for maintaining a 2000 RPM head speed?

[xxxntwv]

As of now my main needle is about 1.25 turns out and the low is just to the lean side and seems to be running OK but still doesn't want to spool up that great but once it does seems to run good