Just installed my C50 into my Shuttle using HHI Conversion mount and clutch adaptor. Checked to make sure everything ran true (statically) and installed into frames. Upon power up, noticeable buzz/vibration from frame assy. Pulled motor from frame and removed clutch and adaptor so motor ran free. Applied slight throttle and discovered that the buzz/vibration as originating from the motor.
The magnitude of the buzz is such that it is more of an audible event than a vibratory event as is felt when holding the motor. It does not go away, but changes frequency with motor speed. While not that objectionable while freerunning, it is quite audible when mounted and the frame assy. starts to resonate as well.
I suppose I was expecting perfectly smooth, basically quiet operation from this motor. Is this normal behavior?