XK K110 premature now voltage cutoff?

[bpjacobsen]

I was just flying my K110 during my lunch hour and for some reason, I was getting about 1 minute of flight time on almost every battery. (turnigy nanotech 300mah) This morning I was getting over 3.5 minutes with juice to spare. WTH? The only thing that I can say that changed was I rubbed some epoxy on the tail boom b/c it was starting to crack. This way, I get more out of it before I have to replace. But I don't feel I put enough on that it should have added enough weight to cause more drain on the batteries. Or is it possible that is what the issue is? Would coating the boom in a thin layer of epoxy really cause this issue? Or what else might be causing this? I would like to point out too though, I tested each battery after light and the lowest one as at 3.8 volts but others were still over 4 volts so the helicopter should not be dying after a minute of flight. It was working fine this morning. I just don't get it.

[Thomas.Heiss]

Hi,

good question.

Maybe a bit too old connectors? But then it probably would not have been any better the next morning.

What was the outside temperature when you tried the previous day?
That the LVC kicks in too early but much juice (3,9-4,0+ V) is left is a good indicator for this, that the lipo has some problems with the current which the motor is asking for.

Make sure to heat your lipos for 45-90 minutes at 38-43/44 degree celcius.

Usually those 1s lipos do not like it very much when the weather gets outside colder (like below 20 degree; you can forget flying when it is only 10-15 to 18 degree celcius).

If you still run into this issue with heated lipos, new lipos and warmer weather:

You could try swapping the 1s ESC.

[bpjacobsen]

Originally Posted by Thomas.Heiss

Hi,

good question.

Maybe a bit too old connectors? But then it probably would not have been any better the next morning.

What was the outside temperature when you tried the previous day?
That the LVC kicks in too early but much juice (3,9-4,0+ V) is left is a good indicator for this, that the lipo has some problems with the current which the motor is asking for.

Make sure to heat your lipos for 45-90 minutes at 38-43/44 degree celcius.

Usually those 1s lipos do not like it very much when the weather gets outside colder (like below 20 degree; you can forget flying when it is only 10-15 to 18 degree celcius).

If you still run into this issue with heated lipos, new lipos and warmer weather:

You could try swapping the 1s ESC.

Seems like it's fine for the most part. Not sure what the deal is. really odd. It's not cold here. It was around 65ish today.

[Thomas.Heiss]

Originally Posted by bpjacobsen

Seems like it's fine for the most part. Not sure what the deal is. really odd.

Any news? Has it got better?
Is the ESC still fine?

How about the BL main motor?
Is there any play on the main shaft? Does the outrunner bell slip out? Can you freely pull it back so there is some play and the pinion gear moves?

I run into this issue on three BL motors from the K110.

Originally Posted by bpjacobsen

It's not cold here. It was around 65ish today.

65F = ~18 degree celcius.
IMHO a bit too cold for those lipos.

Usually it is different (better) when it is 25-30+ degree celcius outside...but when you heat them up for a longer time - even in summer in the evening - then the voltage and max current is more stable as it lowers the inner resistence.

Well, I guess the white Walkera plug is not the very best and the plug at the ESC might wear out over time.