ORIGINAL: squawk7700
I have a similar problem. Here is the senario: Trex 450SE V2/CC PHX45a esc/Align 430XL/2200mah 3s 25C lipo/HS65MG on swash/Futaba 9650 tail/GY401/Spektrum AR7000 w/CC 10a BEC/DX7 Radio.
I only do sport flying, no 3D. All was fine until one day I was not able to bring to a hover. RPM kept cutting back. Had to make major throttle changes on radio from liniar to 0/45/75/95/100. Now I get it to hover and then the RPM drops out. Have to make quick & drastic changes with the throttle stick to maintain a hover but whatever I maintain in this fashion only lasts seconds before another RPM drop.
In an attempt to find the problem I went through the process of elimination. Changed motor, changed esc, changed battery and changed receiver but the problem continues. So the only thing I haven't done was try another radio. My radio works fine with another Trex 450 and an airplane.
Well, what's the verdict? I ran out of idea's and I'm not an electrical engineer.
this sounds like its in your esc programming, maybe you set up both esc's the same. i had a problem almost identical to this, and after going back and really doing a thorough check on my esc programming and what it was supposed to be, i found the problem. i cant remember exactly what it was. maybe the lvc set to high or something. it does sound like your lvc is kicking in too early, so that is what i would suspect. mine would hover for a very short time, then start losing headspeed. then i couldnt get it off the ground. i would try another batt, same thing. i also had a cc 45a esc. plugged it into the computer and went over all my settings, and like i said, i found the problem and its been good to go ever since. but thats definately where i would look.