Originally Posted by
mk13
Next, I tried to improve the entire range with the air bleed. I can see a change in engine speed when opening or closing the air vent, but in my case, the improvement wasn't very noticeable. So I tried the engine with the entire air bleed system removed, and I must say that this engine runs quite well on gasoline with electronic ignition, and that's all. So I'm going to try a flight like this and see if there's a need to reinstall an controlled air bleed or solenoid system.
A fairly decent indication on whether the engine can run properly on its original not modified carb, is to lean the engine to its most optimal setting, and check (with a piece of cloth or filterpaper behind the exhaust) how "dirty" the exhaust residue is. For this you need a stable setting and test after at least 30 seconds of running at that constant RPM.
Then reduce the throttle to wherever you think mixture is worst, leave the engine running for a short while at that setting. Check the exhaust residue again, and check for differences in sootiness of the residue,
Then at that same throttle setting, check how far you can close the main needle and whether running improves.
That will give a rough indication of behaviour in the air.
But I am not very optimistic...
felt pretty good on the ground, but turned out to be barely flyable in the air.