Originally Posted by planekrazy
I've received 3 AP05 motors in three different RTF micro planes from HK. The one that came with the 420 had that issue. In fact the motor can seemed to wobble (spin untruly). In trying to investigate the issue I started to remove the little c-clip on the shaft to separate the motor parts and look at the bearings and what not. As I struggled to get the keep the motor steady and pry the tiny c-clip loose somehow the right parts moved around or seated themselves and all of a sudden without having the c-clip removed the motor shaft started running true
Do not know how or what was wrong originally but that motor still works today, although it has been removed from the Radjet to experiment with other motors and 3S setups. Anyways, hopefully yours will be easy to fix. Have you tried taking it apart and putting back together again?
It isn't my plane. It's a friend's. I think the motor isn't designed to be a pusher. I's designed to pull. I like the way HK state it's a "specially wound motor". It's the same as the a la cart one in their catalog. Whatever.