Originally Posted by IntegrityHndywrk
The things that usually cause this are either the motor plugs/connections coming loose or being oxidized. Also having the battery JST plugs oxidize can cause DC resistance on the battery line. The combination of the two can equal lowered output power or weird things like this. A lot of people used to solder their motor to the ESC directly to prevent issues with those plugs.
BUT, another really strange, but oddly common reason for V120s not spooling up initially is how tight the blade grips are... Try loosening them and see if it helps. I know, it sounds like there is no way.. But you'd be surprised how many people this worked for. Especially when it's the stock motor doing it.
Tried soldering direct with no change, it turned out to be broken wires inside the motor as they exit the stator. I stole the pinion and put on the other stock motor and it works fine apart from nasty sounding bearings and was considering a stab and rewinding but would this little 15500kv spin motor have enough space to wind something for 2s? Is there a calculator for motor kv based on poles size and count people use and trust or whats a reliable way to find what to wind back on it if it can go 2s?
I have an fbl I was going to chuck on my 250 but if I only need an esc and reuse this motor it might be interesting to see that tail sorted and a little more pop.
Also, how sensible is the hp06 1 cell version in this heli compared to stock and is stock pinion ok if so? I have no idea of the kv but it's overpowered for the mini cp so hoping someone has maybe tried it.