I have got my plane back together and did a test run today.

I tuned the engine until it ran fine “in my opinion”.
Then I held the plane inverted for quite a while and nothing seemed to happen.
I flipped it over again and played around with the throttle and then flipped over again inverted and held it in my hand again for a while and this time the rpm dropped quite a bit. I did a few more tests whit all kinds of throttle settings and needle settings. The engine never stopped, but did not sound very reliable.

The plane is stock built, so the tank is there where it is supposed to be as designed. I really wonder if the height of the tank is really that important, the designers are so reluctant about the position of the tank. Many ARF planes have their tank outlet lower than the carb inlet.

About my engine tuning. I could run full throttle for about 14 minutes, with 5% nitro, with humid weather on a ASP .46 engine. Is that about normal? Or am I tuned way to lean? I always fly not longer than 7 a 8 minutes, so I had no idea how long my thank would last.

Also how many bubbles are you supposed to see in the fuel line when running full throttle? I can see quite a few.

Thanks,

Filip