Hi Guys,
Is there any conclusions regarding this 70131/70142 motors? Is there working setups ?
What is more preferred the 70131/70141 ? And also what kv do you recommend for 12s battery ?
Regards
Me
Push the topic, any news on this?
Sorry, it’s too cold and I have no time
Best regards Frank
Hey guys,
My motor just arrived. I chose the MP70141, it will run on 16s.
I’m building a motorized surfboard. NO FOIL!!!
Can someone tell me how to take it apart? I’d like to have a look at the inside and the seals. Mine is potted in the back. However I don’t think its potted very good. There are already gaps between the phasewires and the potting. In addition it looks like the black front and back cap are glued to the red housing. Also the setscrews are filled with potting compound.
Someone really dont want me to have a look inside ;D
Apart from that the motor looks and feels high quality.
Update:
Not sure about the quality anymore.
I can hardly turn the shaft by hand and I can feel it rubbing at some spots on the inside
The setscrews can easily be removed. It is not hard glue. It just some soft silicone. It’s easy to pick out of the screwhead
However the end caps seem to be glued to the red housing.
I don’t see a way to remove them.
If anyone has done it, please tell me
Just tried the motor out for the first time.
Despite the slight rubbing it runs really smooth. After a while the rubbing became weaker. So it must have been a highspot on the rotor.
However another problem occured.
The shaft got quite warm really quickly. Keep in mind the motor was spinning in the air and with no prop. So under no load.
After opening it up (Yes I finally got it open) I could see why the shaft got so warm.
The bearing in the front cap doesn’t turn freely. I can only turn it with excessive force. It was grinding against the shaft and heating it up.
The bearing is glued in. Should I bake the part to get it out?
Otherwise the motor is build really well. The windings are covered with a clearcoat and the highspot on the rotor already corrected itself. In addition to an O-ring the front cap is glued in with silicone.
Only problem now is the bearing in the front cap.
It’s not turning because of the shaft seal right?
If I insert the shaft the bearing turns how it’s supposed too. But its harder to turn then a regular bearing. It feels like the seal turns with it. In addition there aren’t any grind marks on the shaft. My bad.
I have never dealt with shaft seals before. So excuse me if I’m just stupid right now.
Got it disassembled.
The bearing is fine.
Looks like a ceramic shaft seal. And now that I have disassembled one, I understand how they work.
The ceramic bearing is water cooled right?
Should I grease it?
The question remains why the whole assembly is so hard to turn and why the motor shaft gets hot so quickly. I don’t believe the ceramic faces cause so much friction
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2 years ago I take 3 motors from Freerchobby and one of the 3 motors was spinning badly because there was a washer between the stator and the rotor. this is how the motors were assembled so poorly before. I don’t know how now
The shaft will always get warm if running in the air. All inrunners do that.
45-50 degree Celsius , off load on the shaft is normal after 1-2 min and it should not get much higher
Don’t run it to long in the air and I would fill it 2/3 with oil
Ah ok thanks.
I don’t have corosionX but I could fill it with fine mechanical oil
PSA check that your oil is silicone compatible. Mineral oil is ok. Some light CRC oils such as 3-36 are not. They will seep into the motor leads from inside the motor and destroy the cables. Don’t ask me how I know.
Sorry to hear that @jkoljo, what exactly happen?
You can use wurth Corrosion protection spray, crc 6-66 marine and crc hd marine. Personaly tested and none of them are no dissolving rubber, plastic and silicone.
First of all, hello, I think this is my first message on the forum 
I might have the same issue as you did, I used CRC 2-26 and few weeks later it looks like the oil penetrated into the cables but still i do not see any damage. Also in the specification it says that is safe for most type of rubbers.
What did you do at the end, did you managed to save the motor?
Eventually the silicone jacket on the cables will start to swell.
I rinsed my motor multiple times with IPA, let IPA seep into the wires (wires hanging down), then let IPA+CRC come out (wires suspended above motor, and repeated that a few times. About a day for each cycle. When CRC was not coming out anymore with IPA, I let it dry fully and the used mineral oil during assembly. CRC is yellowish so it’s easy to distinguish from IPA on a paper towel below the drying motor stator.
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May I ask what IPA is ?
Isopropyl alcohol or some hoppy beer 
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