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Weird noise....

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Ive noticed this on a few occasions. After I fire up the motors, and slowly raise the throttle, I can hear a high pitch squeeling for a second. it only does this at a certain RPM, and the range is very narrow ..... In other words, It may do it at 1400 rpm, but not 1450, or 1380 etc. I can feather the throttle to try and hit that RPM to hear it, but its easy to go over or under that narrow range that it makes this noise... You think it may be a motor about to fry out?
 

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Ive noticed this on a few occasions. After I fire up the motors, and slowly raise the throttle, I can hear a high pitch squeeling for a second. it only does this at a certain RPM, and the range is very narrow ..... In other words, It may do it at 1400 rpm, but not 1450, or 1380 etc. I can feather the throttle to try and hit that RPM to hear it, but its easy to go over or under that narrow range that it makes this noise... You think it may be a motor about to fry out?
More likely to be a bearing I would say - In the early stages of failure but....... would need to hear it to give a better answer.

IMMEDIATELY after landing, feel that particular motor and see if it is a higher temperature than the other 3.
 
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I am having the same possible issue. If bearing problem, how to replace the bearing?
 

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I am having the same possible issue. If bearing problem, how to replace the bearing?
It is a very easy fix if you have changed out brushless motor bearings before. If you haven't then it is still fairly 'easy' but you just need to be methodical and careful.

Basically, there are two bearings on the Inspire motors, one upper, one lower on the motor shaft situated in the bell housing for the upper and the motor housing for the lower.

Remove the offending motor to get access to the bottom. CAREFULLY remove the e-clip on the bottom making sure it doesn't ping off into hyperspace never to be found again !!!!!!
Then remove the thrust washer.
The motor will now come apart although it maybe a little difficult to separate since the magnets are strong.
Once you have the motor in two you will need to remove the upper and lower bearings. That can be easy in some cases or very difficult in others, depending on tolerance and how tight they are.
DJI use a poor quality bearing in their motors (they always have in my opinion) so get yourself some decent replacements.
They are standard sized 6852Z Metal Shielded bearings available pretty much anywhere on the planet! They can also be known as 685ZZ or 6852ZR
Standard dia: 5/11/5 (Bore 5mm, OD 11mm Width 5mm).
Reverse the whole procedure and enjoy flying again.
Br advised that it is best practice NOT TO REUSE an e-clip more than once. Many do but it is advisable to replace with a new clip each time since they do not fair well to repeated removal and replacement stress.
 
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It is a very easy fix if you have changed out brushless motor bearings before. If you haven't then it is still fairly 'easy' but you just need to be methodical and careful.

Basically, there are two bearings on the Inspire motors, one upper, one lower on the motor shaft situated in the bell housing for the upper and the motor housing for the lower.

Remove the offending motor to get access to the bottom. CAREFULLY remove the e-clip on the bottom making sure it doesn't ping off into hyperspace never to be found again !!!!!!
Then remove the thrust washer.
The motor will now come apart although it maybe a little difficult to separate since the magnets are strong.
Once you have the motor in two you will need to remove the upper and lower bearings. That can be easy in some cases or very difficult in others, depending on tolerance and how tight they are.
DJI use a poor quality bearing in their motors (they always have in my opinion) so get yourself some decent replacements.
They are standard sized 6852Z Metal Shielded bearings available pretty much anywhere on the planet! They can also be known as 685ZZ or 6852ZR
Standard dia: 5/11/5 (Bore 5mm, OD 11mm Width 5mm).
Reverse the whole procedure and enjoy flying again.
Br advised that it is best practice NOT TO REUSE an e-clip more than once. Many do but it is advisable to replace with a new clip each time since they do not fair well to repeated removal and replacement stress.
Excellent!... This is good news. I will prob upgrade all motor bearings. I feel like if I were to send this in, they would not be able to replicate, and just send it back to me, and I would be without a bird for weeks.
 

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Excellent!... This is good news. I will prob upgrade all motor bearings. I feel like if I were to send this in, they would not be able to replicate, and just send it back to me, and I would be without a bird for weeks.
Orrrrrr... if you were lucky they would replace a motor.....but then charge you for it! Bearings are way cheaper to replace and no rewiring required :)
 
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By the way, I have been checking all motors after flight, and have not noticed any difference in heat to the touch.
 
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Thanks Editor!.... I really think this is what the noise im hearing is. Besides, upgrading to better bearings is just cheap insurance. Have you replaced any on the I1?
 
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Cheers for you detailed reply Editor.
I have stripped a motor apart before to clean out debris before but all the extra info feeds into the knowledge banks!!
Everyday a school day and all that.
Gotta love this site!!
 

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Thanks Editor!.... I really think this is what the noise im hearing is. Besides, upgrading to better bearings is just cheap insurance. Have you replaced any on the I1?
I have not (yet) done any personally on the I1, but I have replaced too many others than I care to remember on many different multi rotor platforms.
There are all the same (so far) and I have seen an E800 motor stripped down and it is indeed a standard type brushless, dual bearing out runner motor :)

Good luck, take your time and let us know how you get on.
 

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