On the rear section of the housing, at least two of the holes should be threaded in order to add a duct etc. So first I loosened the housing screws, then I put in the 2 other screws and simply pulled the rear section off.
Hi.
The corrosion does not look too bad. But, by looking at the shaft, and the wear marks I can tell you have some time on that motor.
I’m concerned about the bearing that is in the cap on the end that has the wires. If you look at your rotor you can see where it has signs of rubbing. The epoxy that glues the magnets to the rotor has marks like it’s been rubbing. And if you look in the motor housing you can see signs of this dust on the outer windings.
That bearing back in there is the thrust bearing. Without any lubrication, it may have worn out. How many hours of ride time do you have on this motor?
Pull that rear bearing and inspect it. I suspect you will find it’s worn-out. It’s probably a Chinese bearing. No way a NSK bearing would have failed that fast, even without lubrication.
But seriously guys. Fill your motors half full with corrosionX. This failure never would have happened.
Here is a link to the pics I took of my Flipsky 120kv motor. Both of my bearings were Japan NSK bearings.
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I also filled mine with corrosion x. I rode a few hours and open the motor to check. No water no rust all looks great. The corrosion x is no liquid anymore but a thin paste everywhere. So it will not cause any drag resistance. But how can I get the rotor back in place? It sticks to the side of the housing because of the magnets so I am not able to get the shaft in the rear bearing.
Hi
Firstly, many thanks for your support. Yes the marks are suspicious, this is why I pictured it. I have another pic from back bearing:
I have maybe like 10-15 hours ride time with this motor. Limit was always 120amps current.
How do I pull out the bearings, back one and front one? Do I need to remove those screws to have access?
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Btw I am on side discussion with Flipsky by email. Will let you guys know what the outcome is.
Cheers!
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Is front bearing nsk japan and rear China ?
It looks like, yes. What a weird design decision
Thanks for the advice, Popped mine open and added Corrosion X today. NIce and easy when using 2 m4 bolts in the hub mount to pull on. Not a mark on the casing. Took a good wiggle to get the shaft to pop back in the bearing at the rear.
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What do you think, which option is needed prior to first use:
OP1 - both bearing replacement AND Corrosion X must be done prior to first use OR
OP2- no bearing replacement needed, corrosion X application only will protect from water ingress and also the weak/bad Chinese bearing …killing two birds with one stone somehow…
There’s nothing wrong with the bearings, They may not be the best but there are plenty of motors with large amounts of hours on them that are running well. That would mean they are adequate.
As with anything DIY though, there are probably a couple users that have not got well balanced props. This means their bearings will deteriorate faster than others, and risk water ingress into the motor through the shaft seal.
For these users adding in corrosion X will help.
FR prop runs super smooth, I think this is not the root cause. I had a printed one which was for sure more out of balance but it felt still very quiet and smooth. For the bearings, it would be interesting to know if newer motors also have a Japanese and a Chinese bearing inside. We know already that Flipsky changed the sealing described on their page for the motor:
Since I may have a detective bearing it would be interesting which to chose for replacement. There are plenty with same size and thickness. Ceramic are costy but I do not care about 20 bucks if it will last. The Chinese bearing of 6001z which is in my motor right now is very cheap
All mine have been well balanced. Whether he does it himself or whether they just end up very well balanced, I’m not too sure.
It might feel smooth, but I can guarantee that this is the root cause of your issue. The second a prop is out of balance there is always more pressure on one section the seal which means the opposite side can let water in easier.
Hello FR props ar in 0,01g tolerance
1.) Machining
2.) Polished
3.) Balance
More then 3000 motor units out there and 0 fault on berings
Yea this motor not using high quality berings
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I have just spotted that with very low throttle, my FR prop starts to spin the wrong way, before correcting itself. Still sounds rough until its at 1000rpm or more, MAX RPM (in air) reported on the maytech remote 2800rpm on 10S test battery. I have tried all the timing settings on the seal300A opto ESC. cant say i notice any change.
Since you have both motors, what would you estimate the efficiency of the FR motor is compared to Maytech?
I sure can help with this question. Chinese motors won’t have a better efficiency than ± 70% or a bit more. They are using cheap products and cheap lamination steel. The rotor itself is not even laminated, resulting in lower efficiency.
FR motor should be higher than 85%, my guess, hard to tell without testing it.
More info here if anyone interested to see real results. Not mine though. Someone working at MIT lab :
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