Motor getting power, not turning?

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akrenits   10 mW

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Joined: Feb 15 2016 9:34pm
Location: San Luis Obispo, California

Motor getting power, not turning?

Post by akrenits » Sep 29 2016 5:44pm

Hello ES,

Some of you may have read a recent thread I made lauding the budget super-bike kit from cyclone. I stand by that post, as I have brutally abused it for 300+ miles to date, but this morning my Motor cut out!

The problem: When throttled, motor makes the usual high pitch noise, heats up as usual, even jitters the sprocket gently but wont turn forward. The controller cuts power to the motor after 2 seconds, as if I am stalling the motor intentionally. Interestingly, if I roll the bike backwards and throttle, the motor still has power enough to stop my backwards motion, but will not turn forward.

Not the Problem: Voltmeter throttle is reading, Battery pack is working (my secondary circuits are still powered), connections were all verified to be solid. Since I feel the motor heating up when throttled, I assume my controller is also working properly. In my mind, this leaves the motor.

Before I open up a motor (which I've never done before), does anyone have any thoughts on the problem?

mybike   100 W

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Re: Motor getting power, not turning?

Post by mybike » Sep 30 2016 4:48am

Sounds like stripped planetary gears to me. Open it up and see inside thats the best option.

akrenits   10 mW

10 mW
Posts: 24
Joined: Feb 15 2016 9:34pm
Location: San Luis Obispo, California

Re: Motor getting power, not turning?

Post by akrenits » Oct 09 2016 3:24pm

Not the freewheel or the planetary set. Check out the video and let me know what you think. Not sure what I'm looking at :(
https://youtu.be/6p5Hi2boDyc

akrenits   10 mW

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Re: Motor getting power, not turning?

Post by akrenits » Oct 10 2016 5:05pm

Can you offer some suggestions on my next steps? I know what hall sensors do, but not how they work or how to replace them. At this point I'd be blindly uncoiling things if left to my own devices.

A quick google search tells me im looking for 5v jumps on each wire, but if i dont find that, how do i go about disasembling and inspecting/replacing the sensor?

Is there any way to confirm theres no short in the phase, just to be safe?

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fechter   100 GW

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Re: Motor getting power, not turning?

Post by fechter » Oct 10 2016 7:04pm

To test the halls, they must be powered and you need to turn the motor shaft. With voltmeter neg to battery neg, the positive probe goes to the hall signal lines, one at a time. While measuring the signal, turn the motor. A good hall will alternate between 5v and 0v (well, close to that) as you turn the shaft. Trick is getting the probe on the signal wire. I usually use a skinny wire and jam it into the backside of the connector so the connector can stay plugged in.

If you had a phase short, the motor shaft would have abnormally high resistance to turning, even with the power off.
"One test is worth a thousand opinions"

akrenits   10 mW

10 mW
Posts: 24
Joined: Feb 15 2016 9:34pm
Location: San Luis Obispo, California

Re: Motor getting power, not turning?

Post by akrenits » Oct 23 2016 2:59pm

Hello again ES,

Just found a minute to give an update on my motor. Got readings on my hall sensors finally. One was at a constant .63v, not jumping between 0v and 5v as expected. See the video below for more detail. I'm assuming this means replacing my hall sensor? Again, I know very little about motors, wouldn't even know what a hall sensor looked like if I pulled out the rotor (is that what's next?). Has anyone made a step by step for this issue?

I am forwarding this email to Cyclone's support, who supposedly warranties their motors for a year after purchase against defects such as these. I don't expect much, but will keep you all updated with the quality of the assistance.


akrenits   10 mW

10 mW
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Location: San Luis Obispo, California

Re: Motor getting power, not turning?

Post by akrenits » Oct 23 2016 4:17pm

Yep, referenced the ebikes.ca link from before. Not sure the colors line up with the ones in the pdf, but I tested every combination of terminals out of curiousity. The only one that is irregular is the one in the video. The combination giving the problem does not seem to be the ground wire, is there any chance the circuit board is shot? (or am I just wrong about which the ground is in my motor)?

Either way, just purchased 3 replacement sensors for $9 including shipping from Lyen from ES. Supposedly these will take more heat and abuse then the generic Chinese kind. I plan on upgrading all of them. Hopefully he has them in stock. Figured it would be faster than fooling around with Chinese support, will definitely keep this thread updated on all parts of this.

mafire@email.c   1 mW

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Re: Motor getting power, not turning?

Post by mafire@email.c » Jun 21 2017 12:11am

hi man, i have the same problem now. How you repaired it please?

steamboy   1 mW

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Re: Motor getting power, not turning?

Post by steamboy » Jun 28 2017 2:12am

same problem here.
i write http://www.turbobikekit.com/ where i buy the motor and after 2 days still no answers. then i write directly to Paco at cyclone-tw.com and get this information "you need to replace the hall IC, EW-732"
so far only place where i found EW-732 is this https://goo.gl/zhPsgD but i'm not sure if is the right sensor and how the hell i can replace it.

d8veh   100 GW

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Re: Motor getting power, not turning?

Post by d8veh » Jun 28 2017 9:23am

Use SS41 hall sensors. You can get them anywhere including Ebay.

GIGATT   100 mW

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Re: Motor getting power, not turning?

Post by GIGATT » Jul 19 2018 12:29am

akrenits wrote:
Oct 23 2016 4:17pm
Yep, referenced the ebikes.ca link from before. Not sure the colors line up with the ones in the pdf, but I tested every combination of terminals out of curiousity. The only one that is irregular is the one in the video. The combination giving the problem does not seem to be the ground wire, is there any chance the circuit board is shot? (or am I just wrong about which the ground is in my motor)?

Either way, just purchased 3 replacement sensors for $9 including shipping from Lyen from ES. Supposedly these will take more heat and abuse then the generic Chinese kind. I plan on upgrading all of them. Hopefully he has them in stock. Figured it would be faster than fooling around with Chinese support, will definitely keep this thread updated on all parts of this.

Greetings, Did you fix this issue @ Akrenits?

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