I've rebuilt my quad now with the APM2 and replaced some damaged bits and pieces. When testing everything I spun the motors up to 100% without props and there is a horrible vibration from on of them. A washing machine kinda whir-whir-whir sets in as well.
When testing motor direction it's obvious which one it is - it sounds as rough as a bear's backside. Bearings?
Anyway, if there a way we could disable all but one motor on the quad and still use the throttle (or set throttle position in cli)? This would be handy to test for vibration and work out which motor / prop it is. Removing all but one motor is a tad tedious way :(