Hello everyone,
     I have built a Quadcopter with kk 2.1.5 and here are the specs
F450 frame,
1400kv 2212 9t brushless motors,
30a esc bldc
2200mah 3s  25c lipo battery.
flysky CT6B transmitter

i bought all the parts of quad 2 years back. But built quad with those parts recently and found battery dead and bought a new one. Found one of the motors is 1400kv 2212 10t motor while other three are 1400kv 2212 9t motors. And also i found one esc is not working and bought one esc of 30amp not a similar company but of same config.

Problem is while I'm trying to fly the quad it gets revolving on ground for some time and then topples. I followed all the procedures like setting up kk board,esc calibration,acc calibration,transmitter calibration,standard pi settings all perfectly several times and still end up with same problem. Some times quad flies to little height but it flies to one side without any movement of sticks in transmitter.

I'm unable to trace out the problem and wanted to know what parts i need to replace if i have to fly my quad stable.

here is a video flying my quad:
test1
test2

thank you.

My old cheerson cx10 micro quad does the same thing now.
Gyro issue?

No. Gyros look good. I have checked them. I think there is fault either with esc's or motors. Everything else like motor directions, placing cw ccw props, centre of gravity are all perfect. By the way the whole quad with battery weighs around 700g.

purchased new 2212 1000kv 13t motors and simonk 30a esc's according to suggestions given by expert flyers. Will update after installation and a trail run.

Problem with channels.

Either Pitch or Roll or Yaw is reversed.

Reverse the channel on your tx, all trims to zero.

Remove props and see if corresponding stick movements give corresponding change in the required motors.

Also turn on the self level, throttle up and tilt the quad in all 3 axis(without props), and see if the motors are behaving as required to level it.

Once you achieve that, Your quad will fly flawlessly.

Dont mess around with PI values in the KK board, stock values fly great.

The problem is with combination of 1400kv motor and cheap esc's. And also faulty battery.

bought new 2200mah 3s  battery, 4X 1000kv 13T motors, simonk 30a esc,s.

updated kk 2.1.5 with firmware of RC911.it worked great.

finally it was stable and awesome flying it.

Hi bro....even im building the quad with same things u have build.....i had the same prob that u have shown in video....please help me to clear that bro.......goli.vamsi2858@gmail.com   my mail id please drop out a mail with your whats app number...please help me bro...need to submit this for project

I build a same quadcopter and i need some help.Mail me at himangshusaikia48@gmail.com if you can help