EDIT: Solved. - Anyone know what's causing this grinding / halting at high RPM?

RoninX

RoninX

100 mW
Joined
Mar 9, 2020
Messages
47
Location
Boston
*EDIT* If anyone gives a shit, it was a bad Fardriver. I bought a new on from the legit QS Motor store on AliEx and it runs great now. I know that motor cover should not be loose like that, but it was not the issue, nor is it causing problems with the new 72450 that works right.
Even though the motor is fine, I will never shop at NB Power again. They are rude and muted me a few messages into the convo about the motor issue. AVOID: Company Overview - Changzhou Niubo Power Co., Ltd.

AliEx stores:
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NB Power 3000w 4T. Fardriver 72450. Motor rated at 645RPM. got it set to 625RPM. 80amps / 100 phase amps.
The motor runs fine, until after reaching aprox 30 MPH, the magnets grind and the bike slows down as if I just slammed on my back brakes.

Niubo Power on AliBaba is trying to tell me the motor is fine. trying to blame the phase wires in one sentence. Next sentence my motor is OK. Now "Freya" is completely snubbing me. It's a brand new motor from them. I will never shop with them again.

This is me yelling at them, but it's pointless because the mofos cant even translate English.

This is the motor opened to inspect it.

Thanks.
 
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It shouldn’t be loose like that. Either the bearing is bad or something isn’t machined properly for it to be tight.
Sometimes you can fix excessive clearance with metal shims or loctite.
 
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What controller are you using?
What happens if you raise the RPM limit? does this RPM point where the motor acts/sounds erratic also move upwards?
 
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check for a bad bearing or bent axle. that side cover seem loose as well.
 
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Nothing, but I think In got closer today, thanks to the help from IMHO.
Lowering the phase amps allows me to reach a higher speed before the grind / halt occurs. The lower I go, the more speed I gain. I went as low as 50 phase amps but the bike accelerates like a turtle. Tomorrow he wants me to alter the KI PIDs and run more tests. My current KI PIDs on my Fardriver:
 

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RoninX said:
Nothing, but I think In got closer today, thanks to the help from IMHO.
Lowering the phase amps allows me to reach a higher speed before the grind / halt occurs. The lower I go, the more speed I gain. I went as low as 50 phase amps but the bike accelerates like a turtle. Tomorrow he wants me to alter the KI PIDs and run more tests. My current KI PIDs on my Fardriver:
Click to expand...
but you still have the grind/halt problem. right?
 
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Yea, but I found a way to "trick" the problem. I tweaked the RatiosInSpeed in the Fardriver app so I still have the torque, but once I hit the speed point when it grinds [a quick acceleration to 30MPH], the phase amps are tapered off. So I now had it to where I could reach 40MPH w/o it grinding, and it won't go any faster because of the tweak. well after I shut down the app then reloaded it, it was back to the 30MPH grinding halt issue. I checked the app and my tweaked settings were still in tact. So now I am thinking I just got a bad Fardriver from SaicoSys.
 
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You shouldn't have any grinding no matter how you program your controller. I still think you have a mechanical problem.... Bearing or axle.
 
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Yea, well I just ordered a new 72450 from SaiCoSys. If it still grinds, it's the motor.

Meanwhile on AliBaba, "Freya" from NB Power is snubbing me. Looks like she put me on mute. POS.
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e-beach said:
You shouldn't have any grinding no matter how you program your controller. I still think you have a mechanical problem.... Bearing or axle.
Click to expand...
 
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