OK, I went through fpv files on my computer and was able to trace a bit the reason why it is happening now. I did had blackbox logs from very first flights and it was same situation, back motors were giving 6-7% more power but I think now that this is normal or could be just because the back of the quad is a little heavier. Then I remembered that I did record little bit of a video on my super old gopro on the quad and it did have couple of fast rolls (one of them in the video) which were completely fine, if I did something like that now at the end of the roll quadcopter would be pointing 90 degrees to the right. And then I remembered that 3 days later I crashed (just accidently disarmed it in the air   ). I bent one motor shaft, replaced it with good motor and from that moment I had this problem. I completely forgot that I did try flips and rolls before the crash, all this time I was thinking that probably this issue was present right from the beginning. Turns out that I need to figure out what consequences could that crash cause to the quad. Gyro and accelerometer work fine, checked it in betaflight. Motors are of terrible quality by the way, other than they have magnets issue, they are completely unbalanced (on the product picture there are blue balance weights on the bell and mine just don't have any) and bolts holding bells were completely loose.

I will check on anti-gravity feature, but now I think I should figure out if the crash did damage anything. May be I need to troubleshoot the esc.



edit: I will try airmode first, looked through one of the first blackbox logs again, there is one spot with fast throttle drop and front motors giving 5-7% after that.

this means you doesnt use airmode feature? you disabled it? it would be enabled by default.

the rear motors have to work harder in general, they receive unclean air/ turbulences from the front rotors, which they have to deal with. as lower the angle as more present problematic. 6-7% seems to much.
if your weight isnt centered, adjust it by the battery placement.

troubleshooting and tune improvement is the same route, you cant figure out without adjustements and trys. there is no esc functionality testing tool :-) you can step right to anti gravity feature :-)

(30-Jul-2021, 12:12 PM)hugnosed_bat Wrote: this means you doesnt use airmode feature? you disabled it? it would be enabled by default.

the rear motors have to work harder in general, they receive unclean air/ turbulences from the front rotors, which they have to deal with. as lower the angle as more present problematic. 6-7% seems to much.
if your weight isnt centered, adjust it by the battery placement.

troubleshooting and tune improvement is the same route, you cant figure out without adjustements and trys. there is no esc functionality testing tool :-) you can step right to anti gravity feature :-)

Yeah I wasn't using airmode. I think I turned it off because I was thinking that it was needed only for angle mode. Feel like an idiot now ). Also checked weight balance and actually all this time I should have placed the battery almost half an inch closer to the front, that explains 6-7% bias. Thanks a lot for the tips!

P.S.: attached pictures of the quad, I know that soldering isn't really good but I think it is not very bad as well 

you can hide that situation in acromde too, by not decrease the throttle much.

until you enabled "motorstop", the rotors are spinning at idle too but without airmode feature i-term isnt active anymore on zerothrottle, it doesnt hold the angle and it takes a breath to get in control again when you raise the throttle again. airmode feature is highly suggested for agressive acro maneuvers, like flips...

(30-Jul-2021, 03:02 PM)hugnosed_bat Wrote: you can hide that situation in acromde too, by not decrease the throttle much.

until you enabled "motorstop", the rotors are spinning at idle too but without airmode feature  i-term isnt active anymore on zerothrottle, it doesnt hold the angle and it takes a breath to get in control again when you raise the throttle again. airmode feature is highly suggested for agressive acro maneuvers, like flips...

Got it!   Does make sense. Thanks again!

Edit: Anti-gravity was turned on all this time with default value of 3.5

I ALWAYS fly with AirMode on, personally.  It is a must for me.  Otherwise when you chop throttle for a flip, or a dive, you are basically a flying brick with no control!

AirMode means you are always in control of the attitude of the quad, even at zero throttle.

Some people say AirMode makes it hard to land, but I think that is because they are trying to set it all the way on the ground but while still armed.  I just get as low as I can until I am just about to touch the ground, then hit the Arm/Kill switch. Alternatively you could put AirMode on a switch and turn it off when you come in to land, but I never found that necessary.

(30-Jul-2021, 04:24 PM)MrSolo Wrote: I ALWAYS fly with AirMode on, personally.  It is a must for me.  Otherwise when you chop throttle for a flip, or a dive, you are basically a flying brick with no control!

AirMode means you are always in control of the attitude of the quad, even at zero throttle.

Some people say AirMode makes it hard to land, but I think that is because they are trying to set it all the way on the ground but while still armed.  I just get as low as I can until I am just about to touch the ground, then hit the Arm/Kill switch. Alternatively you could put AirMode on a switch and turn it off when you come in to land, but I never found that necessary.

I always land by disarming, so probably I won't notice any difference )

it feels different, i use acro pure and with enabled airmode feature. aslong as you keep some throttle percentage during the whole flight, there wont be an issue.

Thanks a lot! Now it flies very predictible. Now I need to adjust rates and try turning on rpm filter, but for now I can fly it ). Also I will be swapping magnets in future and try to balance motors with FCs gyro. Will post on that later.

Updates on my quad building/flying. Tried taking out magnets but it ended up to be pretty difficult, magnets themselves chip off rather easily and what i found out is that you can't really use chemicals to dissolve glue, because it can also take off coating from magnets what can change their magnetic properties. So I just balanced them with insulation tape and it came out ok. No jello in fpv feed and gopro videos and it sounds a bit better now.

I'm gonna order some more parts, spare stack for sure and spare motors. Should I buy a set of better quality motors like emax eco 2 or velox v2 or just get couple more of the ones that I already have (jhemcu 2306 2400kv)? Next week there gonna be discounts on aliexpress and eco's will be around 12$ per motor vs 10$ for jhemcu motors. With eco I will need to replace all of them and for jhemcu just to get couple of spare motors.

For the stack I want to buy diatone mamba f4 stack, I am slightly starting to join iflight haters club ).

Ordered emax eco 2, they came out "shocking" 10.5$ per motor with all discounts and coupons. I figured out that in emergency cases I will be able to mix them with my current ones, both are 2306 2400kv

Couple of days ago finally received eco2 motors. Already flew them and good news is they feel almost exactly the same, although I think they give a bit more flight time, need to try them out more to claim that confidently. Overall they do feel like better quality motors than jmt, made from thicker metalls and at the same time weigh the same. Biggest difference noticed, was when I spun them up on my bench, they sounded sooo smooth. Will test them out during this week several times but I think sticking with them for now and ordering spare ones.

There was very noticable jello on gopro video however at fast accelerations, but I think it was due to the fact that I pushed the battery against the mount too hard when strapped it to the quad.