Need some technical advice here for my quad setup. Motors on the front arms of my quad are starting earlier than the ones on the rear. And on flight the quad drifts rapidly backwards. I know drift and motor sync issues are the most common problems while tuning a quad. But I tried many solutions, but none solved my problem. I am really trying to find the root-cause of the problem and not a work-around. I can very well trim the drift using TX trim, but where is the fun without some troubleshooting.

I am using KK 2.1.5 board which is loaded with stock firmware and mounted on the frame using double sided tape.

I tried the following solutions with self-level OFF:

1. ESC Calibration. I had calibrated the ESCs both via KK2.1.5 (standard procedure) and Receiver. Also, I have tested the ESC calibration using a servo tester and found the all four ESC/motors start at the same starting point (1.12ms).

2. Increasing minimum throttle on KK 2.1.5 settings to sync motors start. This solved the problem of motor start sync, but still... Even if I increase the minimum throttle (14),  without lift off, I see that the front motors are running faster than the rear ones. As I am using this without self-level, I dont understand, why throttle in front motors are higher than the rear at ground.

3. ACC Calibration.  Aganist reason, I calibrated the ACC. But as expected, no change in behavior is observed.

4. PI Gain.  Tried with vairous ranges from 30-100. No effect.

Finally, I gave up and tried to trim using TX. Trim works for the first time but next time I fly, the Trim is either high or low.

Quad Config:

• KK 2.1.5 board
• 250mm X-config quadcopter with the following setup
• 2300KV motors
• 10A ESC

Please help me understand the problem with my setup. I am getting really frustrated   with so many failed trials.

@dragons007,
Hope your elevator shows zero in the receiver test in the KK2.1 menu...

reset your PID settings and setup it again
(and don't use double sided tape directly on board coz it may increase resistance or make miss connections due to glue on tape)
i suggest you to foam pad for mounting board and than test..


regards  

hey,
      I'm using Naze 32 rev6 flight controller and cleanflight, while flying my quad one of the motors stops spinning while in flight after increasing the throttle beyond around 50 to 60%. But this doesn't happen without propellers mounted on the motors.
I have calibrated the board, tuned the PID values, calibrated the ESCs.

Components used are
1. 450 quad frame
2. four a2210/10t 1400kv brushless motors
3. 30 Amps ESC from ebay(without any name)
4. 1000mAh 30c battery
5. 10x4.5 propellers
6. Avionic 6ch transmitter

I'm stuck here for weeks now. please help

kk2.1.5 is very unstable.I also faced the same problem but after upgrading my f450 quadcopter to naza m lite it flied well.I am using emax 2213 935 kv motors and emax esc 30a .I got 9 minutes of flight time with 3s 3000mah 40c battery without gimbal and camera.