Noobie here, extreme resistance in hub motor wheel

[waratte]

Hi again, I have a new problem with my new motor. At first my ebike ran very well, clean, quiet, and fast, with only one hiccup.

Sometimes when I started my ebike and hit the throttle, the motor spinned but it met massive resistance, causing me not to gain any speed at all and my bike vibrates loudly from trying to overcome the resistance. Usually, the problem would fix itself after 5 minutes and the bike ran clean like normal after that for the whole day.

Now, it seems that the resistance has increased so much that all the wheel does is jerk forward about an inch or so and stop moving and it hasn't gone away yet. Every time I hit the throttle, the wheel just jerks a little bit then stops. This happened after I was rolling backwards down a flat sidewalk and tried to stop it using the throttle.

Also, I have noticed that it has become really hard to pedal. Before, I felt like I was pedaling with no resistance from the motor, now the resistance is pretty strong and causes my bike to vibrate as I pedal.

Anyone know what has happened to my motor and is there any way I could fix it?

This is the motor I have by the way: link.

If I can't fix this problem, could anyone point me to a more reliable kit or motor I could replace that one with (preferably as easy to install, similar specs, and a hub motor too)

 

[MadRhino]

Fix it before you fry the controller. You probably have a phase grounded, that is the most common reason for what you describe. Check all 3 phases for continuity and impedance, between each other and also between each and the motor casing. Once you found the fault, inspect the wire for insulation wear, this could be on the bike or inside the axle channel.

 

[waratte]

Fix it before you fry the controller. You probably have a phase grounded, that is the most common reason for what you describe. Check all 3 phases for continuity and impedance, between each other and also between each and the motor casing. Once you found the fault, inspect the wire for insulation wear, this could be on the bike or inside the axle channel.

Hmm, I'm not very experienced with electronics and such. What do you mean by me having a "phase grounded"?

 

[d8veh]

I would say that it's too late. You've already blown a mosfet or two in the controller.

Turn the motor by hand with it connected but switched off. Is it hard to turn. Disconnect it from the controller. If it's now easier to turn, your controller's had it.

 

[waratte]

I would say that it's too late. You've already blown a mosfet or two in the controller.

Turn the motor by hand with it connected but switched off. Is it hard to turn. Disconnect it from the controller. If it's now easier to turn, your controller's had it.

Yep, that's what happened. :/

Any idea what caused this? I did noticed my controller was very hot when this happened.

Also, any idea what I can do to prevent this? And where can I get a new one?

 

[Ykick]

The juddering (shaking, low power) was your warning to STOP riding it and locate the problem.

Whenever Phase power isn’t synced with wheel position via Hall sensor switching signals or other (sensorless) electronics - the power tries to go somewhere and it often reflects back into whence it came. The resulting electrical “collision” often damages power transistors (FETs).

For replacement you can use any number of generic controllers. But you’re gonna need to be able to determine if Hall sensors in your motor failed, maybe bad connector, damaged wires, etc? Otherwise, the same thing may just happen again.

Plus, to use any number of generic controllers you’re probably going to need to learn how to determine proper Phase power - Hall sensor signal combinations.

There’s simply no standard color code between motors/controllers and it’ll just drive you nuts trying to keep track of it. Much better off just learning how to “find” proper phase/hall combinations without cooking your electronics.

Here’s some links I prefer for this topic:

http://www.ebikes.ca/learn/troubleshooting.html

https://endless-sphere.com/w/index.php/Determining_the_Wiring_for_a_Brushless_Motor

This has happened to a lot of people.

 

[waratte]

Hmm, that's really weird as it was working fine before... Where would be a good place to look for generic controllers?

 

[d8veh]

These things often start with something simple, like a loose connector, which stops the motor from running smoothly. If you try and run it like that, you will damage the controller.

Moral of the story: Never try to give your bike full power if it's not running correctly.

 

[Ykick]

I use Lyen modified controllers. Pricey but I like many of the touches he adds to them, fast shipping from San Francisco, programmability, and his support has always been nothing but stellar for me.

EM3EV is another good source of programmable controllers but you’ll pay a little more than eBay while waiting for a shipment from China.

On the cheaper scale - here’s several eBay listings of which many would work for your motor - http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR3.TRC2.A0.H0.Xebike+controller.TRS0&_nkw=ebike+controller&_sacat=0

Practically all of them you’ll need to ignore color codes and figure out the proper combinations for operation. And remember, you may still have a bad Hall sensor and/or nicked wiring with your motor?

Some folks swear by an eBike tester - http://www.ebay.com/itm/New-24V-36V-48V-60V-Electro-Car-E-bike-Scooter-Brushless-Motor-Controller-Tester-/351119106382?hash=item51c054614e

I don’t bother with tester but I know enough to test my gear using a DVM. If you don’t have a DVM then you probably should get one of those too.

I would also suggest you grab a watt/power meter like one of these -
http://www.ebay.com/itm/GT-Power-LCD-130A-High-RC-Precision-Walt-Watt-Meter-Power-Analyzer-Ver-2-NEW-US-/331215821510?hash=item4d1e005ac6

To insert the power meter you’ll also need some connectors (that’s a whole ‘nother can of worms, btw) I use APP (Anderson Power Pole) but some folks are happy with Dean’s, 4mm Bullets, XT60’s - the main thing to avoid automotive connectors. RC Hobby stuff is where to shop connectors, crimp tools and wire.

If this is getting too far above your head then perhaps post your city location and someone might be able to help you sort this mess out locally?

 

[jesusjesus]

You could get a controller that has self-study function, it will auto adjust the wiring.

 

[dogman dan]

My guess is that you have a damaged wire to the motor. When the two fat wires were making intermittent contact, it would run shitty when shorted, but then when not in contact it would run ok. Eventually, shorted wires blew your controller, as it will do.

So you might have a close look at those wires, might have a cut or melty spot where it enters the motor, or a problem at the plug.

 

[Baron]

Hmm, that's really weird as it was working fine before... Where would be a good place to look for generic controllers?

I would message the seller and ask to buy a new controller from them. That way you know it's guaranteed to work with your setup, and you don't have to worry about phase/hall combinations, different wire connectors, or other unforeseen problems.

I have the same exact kit but purchased from xcceries on ebay. My lcd display wasn't working when I first got it but I messaged them and they sent me a new one for free.

 

[d8veh]

Don't buy anything until you're sure about the cause of your problem, otherwise your problem might repeat.