Quadcopter using (Pixhawk 4) Motor 1 and 2 are heating up and motor 3 and 4 are fine

Hello everyone

Today I did a first flight test with quad rotor (pixhawk 4) successfully. Flying is good.

  1. But the motors temperatures are not same. Motor 1 and 3 gets more heat than the other two ( Motor 2 and 4 are temperature is fine).
  2. When I take-off in stabilize mode the drone was slightly rolling to left side but as soon as I put loiter, its became stable and hold its position. I flew drone continuesly for more than 30 minutes.

Things used

  1. 450 frame
  2. 30 emax esc
  3. BLDC 935 kv
  4. 8 inch prop
  5. 4s battery 3700 mah
    Please let me know what shoul I need to do solve motor heating (1 & 3) problem.


Post a link to the .bin flight log.

Here it is


Please let me know


That link requires Access. remove that requirement for help.

Hi Dave,
now you can abel to access.

Please check it.


You need to let EVERYONE have access to your log file.

I made it like that only. Anyone can access.

The link is not working.

Updated link
Kindly check and let meknow


Hi Gazer

I am facing one more problem

I made RC failsafe as Always RTL, but when I switch OFF the transmitter on loiter mode it remain keeps the position hold not performing the RTL.

Could you tell me what should I need to do to perform RTL with TX off.


Fsi6x transmitter

Check the documentation for your receiver failsafe actions, it will probably be “hold all existing outputs” or something similar. You may have to bind the receiver again while the transmitter throttle channel is set to something like -110% (in OpenTX terms) or about 970 PWM using trim. Then set the transmitter throttle back to normal after binding and test the failsafe on the ground.

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There’s a significant physical yaw/motor imbalance like motor mounts are twisted on the frame, or the frame itself is twisting. People have even found CW and CCW props are not always producing the same amount of thrust.

Your clock-wise motors, 1 or 2, will be twisted on the frame, and motors 3 and 4 have to work harder to counteract 1 and 2

Yaw is not tracking so well because of the motors being twisted on the frame

You’ve got some high vibrations there, you will want to look at prop balance and also antivibration mounting of the flight controller. Secure any loose wiring too.

I suggest you dont stop at the yaw problem though!
You’ve got a lot of default values there. You really need to use this spreadsheet or the MissionPlanner plugin ( Alt A on the keyboard) to set some parameters based on your quad, and then run through the tuning guide.


Since you said it rolls after you launch, you might want to redo the accel and RC calibrations again.
Check you transmitter trims are NOT set, but all centered.


Thanks Shawn.
Will test and get you back…

I did exactly what you said.
Now RC failsafe is working.

Thanks shawn.

Dealt with this as well. The motors are quite sensitive to being just a tiny bit rotated. Took me a number of flights to get the thrust so its pointed straight down. My bubble level would say it was level but the logs said otherwise

Thanks for mentioning props might produce varying thrust, Shawn. I hadn’t considered this and been using cheap props as I had a couple mishaps early (thinking I would switch to better props when I ironed out everything).

Hi Shawn,
As per your suggestion

  1. Used plugin and updated some recomended parameters.
  2. Did accelemeter calibration.
  3. I did not used any antivibration mounting. (need to get) For now using Double sided tape only.

I went for a test flight with all changes above

  1. Loiter is performing is good. holding its position perfectly.

  2. Rolling problem is fixed. Motor (1 and 2 ) heating problem is also fixed.

  3. But some time VIBE is becoming red color when I move the drone in the air. Here is the log file…

Is that fine? OR Can I reduce the VIBE if I go for AUTO TUNE?

Please le me know.


The vibrations are a physical problem and you must definitely fix them before going to autotune.
It is risky to fly in anything other than Stabilise mode if you are getting vibration warnings.

Once you have vibes fixed, you can set up Harmonic Notch filter properly and do Autotune. We’ve got a 700mm/2.5kg quad with V5 Nano that performs like something half it’s size after that process. Elsewhere I might have called it a 650mm frame, but I measured it and it is really 700mm.

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Thaks shawn.

  1. Could you please suggest some antivibration module?

  2. Also I am using F450 frame. Is that fine? I suspect the frame only.

Those frames are a bit too flexible and can enhance the control issues - but they do usually work in the end.
You will probably need to balance all the props (usually evident in X and Y vibrations) and maybe improve whatever is mounting the flight controller now, something like in this discussion:

Since you are using the Pixhawk 4 from Holybro it looks like on their web site they just use/sell the foam mounting pads. That may not be enough, or you might have done something wrong.
Make sure the wires aren’t pulling tight on the flight controller, rubbing against it or vibrating around unnecessarily in the prop wash.

Also keep in mind if you add weight, like a camera, you will probably need to increase the prop size to 9 or 10 inch.

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