Long post with decent information is far better than a short post that doesn't mean much
Since your gun actually cycles (2 trigger pulls or whatever)...it sounds like it could be 1 of 3 things...or a combination of them.
1. Your battery is not fully charged
- easy remedy...charge it up fully, use a known good battery, etc...
2. Your motor height is not set correctly
- adjust the screw in the center of your grip...all the way in, back it out a couple of turns and listend to the shot. When it's as quiet/smooth as it gets...that's the best you're going to get. When you get close...just make small adjustments
- you don't have to fully reassemble the gun to set this...you can put the mechbox together and screw the grip direction onto the mechbox. You should still fine tune it once the whole AEG is assembled though.
3. You messed up the shimming
- you may have put too many shims on a gear, essentially jamming/squeezing it too tight.....the only fix to that is to reshim it properly.
- you have to readjust the motor height after reshimming....maybe not by much though. See #2
* there is no such thing as timing...as long as the nub on the half gear (in your case it's more like a curved bar...on most it's more like a post) is in front of the tappet plate fin (white triangle piece positioned on the gear)....you're good to go.