Quad constantly flips during takeoff, motors not spinning the same speed

Hey guys so I’ve been gone a while about 9 months and have decided to get back into it and get my quad flying again. Here is a quick rundown on what I got.

Frame is a modified X650F from hobbyking. Modded to where I run 15in props on it and also run it on 6s. I use Afro 30a ESC flashed with BlHeli. PIxhawk FC, Frsky x6r RX, Taranis, Motors are Turnigy Multistar 4114, 330kv.

I updated the pixhawk to the most current FW last night and went back through the setup. My ESC’s are oneshot capable but I have it set to regular PWM mode. If oneshot is enable I get the issue where it takes a while to arm and different motors arm and different times.

So here is what I got going on. Took it out last night to get an autotune in hoping I wouldnt have problems well, armed it and started to increase throttle as soon as motors start to spin it did a back flip and broke a prop. Put a new prop on it. hooked it up only to 3s and took it outside again. Armed and started to increase throttle again and noticed that one of my motors were not spinning as fast as the others. So I picked it up off the ground and held it in the air and increased throttle again, I could feel the front wanting to pull away from me but the back was a different story.

No I am here writing this post. I had a suspicion that I have some bad ESC’s but am not totally sure. I’ve included a dataflash log you can see where I picked it up and I never provided any other input but throttle. Tried all of this in stabilized mode. Please help, this was the reason I took a break 9 months ago. Just go so irritated with it that I had to. Thanks in advance for any help you guys can offer.2017-04-16 13-57-20.bin (1.3 MB)
2017-04-16 13-57-20.log (2.9 MB)

Here is another log showing what I consider to be a major issue. I think I got it to quit flipping at least it hasnt on me again since. I re-did ESC calibration for the umptenth time and also went back to normal instead of Oneshot. Now as I am throttling up It gets such bad vibes that the pixhawk which sits on top of my quad mounted to an anti vibration mount looks like a big black blurry circle. My motors get super hot to with less than a minute of them running. I have lowered P gains On pitch and elevator to .080 and I gains to .060. 2017-04-16 18-03-43.bin (1.2 MB)

I haven’t seen this pattern since I compiled my own version of the firmware and it started to go crazy. Any way the vibrations are oscillating which is not good. Perhaps the mount is too soft.


I will take a video tonight when I get home from work. I have taken the mount off and tried it with the pixhawk mounted to the frame same thing happens. Also before the flyway happened it would fly fine with the mount.

I found my issue. Apparently the ESC’s I had on it do not play nice with large, high pole count, low KV motors. I had Afro 30a flashed with Blheli. What I got to replace them are Hobbywing xrotor 40a. Works like a dream now and I couldnt be happier. I have been fighting this issue since late spring of last year, and couldnt get find anyone with any knowledge of this. I am using turnigy multistar 4114 330kv motors spinning 15inch folding props. Vibrations are basically gone now as well. cheers!