Originally Posted by johan_alps

When you say check you mean change them and test the flight time?

Doing that means I'l have to change the connectors of all my batteries as well right? I would love to have missed something here

Yes you change everything over micro Deans.

I see you have a volt meter.. so after the heli lands because it can't fly any longer check the battery voltage if above 3.8V. And also is the recharging time shorter now than when the batteries were new.. Al point to a bad wire that limits the flow of power to the heli at the connection.. due to some of the wire's strands being broken..

Originally Posted by johan_alps

Wow really? The brushes wear out to a point where it consumes almost 2 times more energy?

Yes. My last Genius CP motor was like that. Battery barely lasted more than a couple of minutes and the motor gets insanely hot until it eventually melted the frame. I'm keeping a close eye on my current motor, new frame has the new motor impressed on it (frame is softening) but hasn't actually melted so far.

The mini CP has a temperature gauge right? What does it say? When the motor uses up twice as much power without adding more torque, that energy has to go somewhere. If the heat hasn't changed, then the battery may really be just losing power.

You really need to tell us how many flights that the motor has had and also how many cycles each battery has gone through.

For a start, the stock batteries are very bad and It is not a good idea to run the battery until the heli drops.

@livoniabob Indeed recharge time is very quick, less than half an hour for most with the stock usb charger, where it was longer when they were new. I did measure end of flight voltage once and it was 3.8V if I remember correctly. I'll have to wait a couple of days until a spare tail motor arrives so I can check it along with the charging time again.

Indeed one wire has some frayed strands, but it seems that more than 50% are still there. I'll resolder as soon as I get a spare connector.

@Hajile Not sure if it has a gauge, should I be able to read it on the transmitter? Nothing molten yet. I can almost touch it after flight so probably below 100 celcius.

@zadaw A rough guess would be 20-25 cycles for some of the batteries, about 80 flights in total.

@All
It seems like I did most of the no-no's with lipos, flying for too long and storing them fully loaded ... I've ordered some new batteries and I'm keeping an eye on http://astroid-designs.myshopify.com...ctions/walkera for their brushless upgrade kit.

I'll keep you updated when they arrive. In the meanwhile thank you all for your time! It has been quite instructive so far.

Originally Posted by pmerritt

Internal Resistance of the battery

So I did measure the internal resistance of one of the batteries and it is 0.27 ohms (voltage dropped from 4.06V to 3.80V with when a current of .95A was flowing through it). So I believe it is no wonder I have short flight time. I'll tell you wether new batteries completely solves the problem or not.

Originally Posted by johan_alps

So I did measure the internal resistance of one of the batteries and it is 0.27 ohms (voltage dropped from 4.06V to 3.80V with when a current of .95A was flowing through it). So I believe it is no wonder I have short flight time. I'll tell you wether new batteries completely solves the problem or not.

I would recommend that you set up a telemetry linked alarm so that it goes off when the voltage goes below 3.8V. The bigger 350 mAH batteries are also better.

Originally Posted by zadaw

I would recommend that you set up a telemetry linked alarm so that it goes off when the voltage goes below 3.8V. The bigger 350 mAH batteries are also better.

But that will kill my flight time as I understand.

Anyway, received a lot of parts the other day.

- replaced engine
- replaced wires and resoldered from the circuit board to battery
- tried a new battery

each one of these all of these actions made things better. I've yet to measure the time, I've been so happy flying around.

However I tried to install a brushless upgrade, but it was a failure. Sure it turns but I wouldn't be able to lift with it, so I put some info in the above thread that looked the closest related.