I tried changing the plug and using larger, thicker fuel lines every where outside the tank, it idles ok until the gov kicks in then goes to rich then shuts off. I re tuned the high mid for sound, smoke and optimal power, but idle to normal is poor, I do not want to touch those needles just get a better idle into normal flight. I tried leaning idle needle .5 deg each time but it just gets irratic and looses smoke.
I got desparate and started richening the idle needle but that just made it shut off immediately, even when i raised the idle.
Something I noticed is, fuel bubbles are constant in regulator line even while the heli is just sitting idling with no flite.
I took apart a pump on my old 91SRS and noticed it had the same type of diaphragm as the DRS carbs, could it be that the YS regulators have air leaks around the diaphragm into the reg.?