# Why does motor not want to go above 2/3 thrust?

This is related to my past ESC troubles. See link for some flight history.

I tried the recalibration as suggested by ifconfig, which sadly didn't work. But now the motor will not go above 2/3rds thrust(slight improvement), no matter the calibration range. I did do one calibration where I used full throttle as max and the center as none, and the ESC would stop working once I got above 2/3rds of the calibration range.

What it is not;

• ESC overheating/overloading(it is cool to the touch and I even ran it in our deep freezer, same results)
• broken ESC(I used a new ESC as well as an old one I fixed. Both have the same problem)

• the receiver has been in some crashes, perhaps it got shaken around and is messing with the signals?
• the transmitter is cheap so it might be messed up, but it was working fine before.
• motor might be broken but I don't think so, it's not even scratched up.
• battery(charger) might be to blame. The charger I have (also cheap) has 3 lights for the cells, and the cell 1 light never turns green(ive left it charging overnight, still red). I just thought the charger was broken, but maybe cell 1 isn't getting charged?

hardware specs;

• ESC is rated for 30A, uses T-plug to connect to battery.
• Battery is a 3S 2200 mah 30C from Mirahobby
• Motor is 2200 kv, is using a 9050 prop(slightly outside plane and motor recommendations)
• Plane is an FT Spitfire from flitetest
• The only modifications I have made to any of these pieces is when I globbed some hot glue onto the antennae on the receiver to strengthen it some

What do I need to fix to get the motor/esc to work properly? Do I need to replace any of my hardware? Should I just build a lighter plane that only needs 2/3 thrust?

• Do you have a multimeter? If so, could you test to make sure that a fully-charged battery is 4.2V*[cell count]?
– ifconfig
Dec 9 '20 at 18:10
• @ifconfig, I used to have a multimeter, but it broke when i used it to test an electric fence(tip; don't do that). I have yet to purchase a new one. also I will add in the cell count, thx for reminding me of that. Dec 9 '20 at 18:39
• Okay, well you could also check the transmitter endpoints to confirm that the TX/RX are outputting full-range values.
– ifconfig
Dec 9 '20 at 18:55
• A possibility is that one of the cells of the battery is damaged and cannot supply enough current which results in the ESC cutting out when it draws too many amps.
– Jacob B
Dec 10 '20 at 4:00
• You really need to try a different battery, especially as it's not charging properly. Maybe even a 12v car battery? Dec 10 '20 at 8:32