I built a fy680pro hex.Controller 3dr pixhawk.40 amp esc’s,620kv motors.4s battery 5000mah.13x5.5 props(carbon).
here is the issue: I have avery hard time flying in any mode.throttle management is almost uncontrollable.I just barely raise throttle and the aircraft just wants to climb fast,Also,when landing it drops like a rock.I can hover but very touchy and over sensitive.Any suggestions will be appreciated,
SOLVED.
Changed from a 4s battery to a 3s battery.Not overpowered anymore.
Mine is about the same, but have 700kv’s. With 13" props was kinda overpower, hovered at 22% throttle, lol. Switched props to 12", much better, better control, and 3 minutes longer run time .
Glad your hex flies better with 12in props. :mrgreen:
I have 415kvs with 13" and it hovers below at around 46, running 6s…
By any chance did you tweak your Throt_Mid setting??
I did adjust mid-throttle. In my case mid is 57%. How’s it going for your set-up? :mrgreen:
Try to get approx 50% if you can.
It’s going pretty good… Managed to try out all the flight modes I was intersted in… Stab…Loit…althld… drift<---- too much fun!!.. Tomorrow morning when the winds are calmer I’m gonna try to zero in on the 50%…
I’m running an APM 2.6 by the way… Couple months from now I’m going to upgrade it to a Pixhawk…
I’m definitely learning as I go.I would like to point you to a couple of guys on you tube that have excellent tutorials for apm 2.6 and pixhawk etc. Dennis baldwin and Peter King (u.k.) 
Yeah I follow those guys… The ones from CPO are good as well I learned alot from him as well… Happy flying!!