weird motor issue at higher speeds modified dyu d1

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daveyjones97   10 W

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weird motor issue at higher speeds modified dyu d1

Post by daveyjones97 » Oct 14 2018 2:50pm

Hi guys, been on a hiatus with internet forums since I got told to tig weld something mundane on a MIG welding forum...
Anyhow, since I snapped my 2wd ebike in half doing some urban moto x I found I hardly use my sensible dyu d1 as it feels SO slow now and I use my car instead. So having promised myself I wouldn't mess with the dyu, I took it apart and ordered a 6fet sensorless 4110 controller from em3ev. It runs 15s (62v max) 30a phase current 10a rated current which I set in the em3ev software. Originally dyu ran 10s 42v max rated current 7a, max current 12a, read from label on oem controller. Wheel motor says 36v 350w and has no hall sensors.

The Problem; at around 60% or more of max speed unless you accelerate gently you get a sudden grinding noise and feel from the motor as if all 3 phases had been shorted (don't ask how I know). Back off a bit and it gets better/goes completely. The strange thing is full throttle is flawless up to 60% speed and also if you gently accelerate around this issue you can load the motor up again and it acts fine. Once you get past the issue you can maintain speed up a hill that would be = amp loading to the rate of acceleration that would cause the grinding and not have any problem.
Also worth mentioning is when the controller came it was set to 70a phase 30a rated current. May have forgotten to adjust this down on 1st test ride :shock:
I have no idea frankly whats wrong and could live with it if I had to but would be really grateful if anyone knows what this could be and how to fix it. Thanks

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MadRhino   100 GW

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Re: weird motor issue at higher speeds modified dyu d1

Post by MadRhino » Oct 14 2018 9:22pm

daveyjones97 wrote:
Oct 14 2018 2:50pm
... Wheel motor says 36v 350w and has no hall sensors.
...
Brushed?, geared?
Your problem probably can be fixed, but is the motor worth it? 100$ would buy you a better one. If you need parts to fix yours, with the time to fix it, you will be paying a new, better motor after all. And that is in the case you can find the parts in the first place.
Make it fool-proof, and I will make a better fool.
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daveyjones97   10 W

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Re: weird motor issue at higher speeds modified dyu d1

Post by daveyjones97 » Oct 15 2018 6:16am

Thanks, don't know if its geared or not, would assume not as its a cheap bike and a 12inch wheel. Also reluctant to change the hub motor as the wheel is cast not spoked. The wheel size is quite unusual. Prolly have to just open it and look for damage.
Will likely just live with it rather than try and change the wheel. This is meant to be my dependable backup bike.

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fechter   100 GW

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Re: weird motor issue at higher speeds modified dyu d1

Post by fechter » Oct 15 2018 9:20am

That sounds like a strange problem. It does not sound like anything we typically see. It seems that possibly the hall signals are getting interference. Double check the hall sensor wires and connectors, especially the ground wire.
"One test is worth a thousand opinions"

markz   100 GW

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Re: weird motor issue at higher speeds modified dyu d1

Post by markz » Oct 15 2018 9:30am

Grinding Noise and Hall Sensor Mix Up would be two separate things IMO
Grinding noise would suggest if you had a geared motor then the gears are pooched, on a dd then could very well be the bearings as I had the same grinding noise, but the suggestion of 60% throttle could be halls, throttle, controller pooched.

Is it a KT display type?

daveyjones97   10 W

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Re: weird motor issue at higher speeds modified dyu d1

Post by daveyjones97 » Oct 15 2018 12:12pm

Neither the original or the em3ev 4110 contoller have displays, had to get an optional program cable to change settings. Also is and was sensorless.

Think il wait til i get a puncture or the issue gets worse and take it apart. Does feel like phase shorting more than a gear slipping but thats just gut feeling.
Thanks

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