Awful loud squeal?

[Longbaorder23]

Hello all,
I just bought some motors for a mini quad project I'm doing, and I've come across a problem. At about 75% throttle there is an AWFUL LOUD high pitched squeal emitted from all motors. At about 50% it starts, and gets louder the faster they spin. Then towards full throttle the noise gradually fades. It's REALLY loud. All motors do it equally. Escs worked fine previously with other motors. Happens with and without props. Bad bearings? Don't know what to make of it. They appear to spin fine by hand, and connections are direct soldered, no bad connections. Way to fix this? If it's bearings I can go buy upgrades. Suggestions? Confused... Thank you!

 

[Balu]

What ESCs and what battery are you using? 4S, 3S? Perhaps you can upload a video or something where people can hear the sound it makes?

I didn't have that problem yet, but bearings sounds reasonable. Also I've heard people saying that a "chirp" noise can come from a desynced esc/motor? But that's just a short chirp, not a continous squeal?

What do the professionals think?

 

[Longbaorder23]

turnigy plush 10 amp on 1600mah 3s. definitely within the motors voltage range and escs voltage range and all...

edit: turned timing to low, testing again now... hm.

 

[xuzme720]

The Plush do have a timing adjustment so it might already be solved for you, but for others that might have a similar issue, Timing, or more accurately, having an incorrect timing setting on the ESC can create a sound remarkably similar to a bad bearing. With so many ways to program individual ESC's, the best bet is to consult whatever manual you can find for your particular brand, or use a programming card, if you find your motors making this noise but showing no other signs of bearing failure.

 

[rcflyer729]

I am no expert but I think it is the esc try using a different esc if u have one and see if it goes away

 

[Longbaorder23]

ill test another esc then. adjusting the timing did nothing except extend my flight time a bit. the noise persists only at certain high levels of throttle...

 

[Craftydan]

LB,

Specifically, which motors are you using?

Some of the high-pole-count mini motors do not play nice with traditional ESCs, and they tend to de-sync. unfortunatly, the only suggestion I have involves a special varient of simonK ROM and the plush series no longer supports simonK. The plush ESCs can take a BLHeli ROM, and it wouldn't surprise me that the mini-motor ROMs have been built for it, but I've got no experience wiht BLHeli to help.

When it starts squeeling, stop. The sound you're hearing is wasted energy (either in a bearing or a motor rapidly accelerating and decelerating between each phase change), and wasted energy means heat . . . which is the primary mode of failure in an overworked motor.

 

[Longbaorder23]

using these:
http://www.hobbyking.com/hobbyking/store/__24239__D2826_6_2200kv_Outrunner_Motor_US_Warehouse_.html

not sure what the problem is... im planning to replace the motors though. im concluding that the mismatch is the motors, not esc. plush escs have worked great for me for years, with other motors. im looking at a set of turnigy propdrive motors, they look promising.