Hub motor noob can't get rollin!

Freeze

1 mW
Joined
Jun 8, 2016
Messages
10
I've been riding my Currie US Pro Sport Ebike since about 2008 and it still runs but when I got the chance to bid on a modern Diamondback with a rear hub conversion on it on ebay, I went for it and won! The bike came with a 36v Ampedbikes Stealthy kit and LiPo batteries. Bike arrived assembled but a bit rusty. Got cleaned up and batteries charged. Have full power (3 lights) to throttle. Motor will not run. When applying power from throttle, motor, cable and controller will get warm. Wheel spins freely by hand but, not in reverse. After some research. I'm assuming this is a geared brushless motor since I cannot back up. I cannot get the motor to run at all. The switch is on, the button on the controller is in. No hum. no jerking, nothing, just gets warm. Thanx.
 
Aloha, not knowing anything about the Diamondback, it seems to me that the hall/phase wires are not correct. I would not be trying it out until the motor "gets warm", as this can damage it. Just switch the yellow/blue/green combinations and try throttle for an instant to see if you get a change. (you have 36 wire combinations). Unless someone out there is familiar with the specific Diamondback and there is no possibility of wires not in correct order, then it is beyond me.

francis
 
Hi Francis, thank you for the reply! This was advertised as a working bike. The Diamondback had the conversion before I got it and had been ridden. I checked all the connections from the controller.
 
Possibly when shipped the wires going into the axle might have gotten skinned up and are shorting out ? I would start there and maybe try to separate them before putting throttle to the bike, again.
 
If the resistance turning by hand backwards is very bad, there is a short.

Might be in the wires, as said above. Might be the controller is blown.

Unplug the motor from the controller, if the hard resistance gets a lot easier turning backward, the short is in the controller.
 
Hi Dogman, thank you for your help. With the battery and motor completely disconnected, I physically have to lift the back wheel off the ground to get the bike to roll backwards on the front wheel. To clarify, if I put the original, non motorized rear wheel back on the bike, it rolls backward just fine. I read somewhere that geared hubs don't roll backwards. Maybe I misunderstood, because the video shows my motor rolling backward sand I thought my Ampedbikes Stealthy is a geared hub. I never thought this was normal.
 
Hi Nelson37, thank you for the clarification on the motor. The bike was fully assembled when I received it. I had to get a charger and learned a bit about LiPo batteries. I charged the batteries and went from there. Let's just say I got the bike at such a good price, I'm not sending it back! I had the wheel off the bike and disconnected. The wheel did not want to spin forward or backward from the axle. After some Liquid Wrench and some coaxing, the axle now turns forward pretty easily, Backward however it's totally stuck. Also worth mentioning is that the bike was ridable minus the electronics. Because of the sprocket, I was able to coast and pedal. I can only hope freeing the axle to move forward from the hub when it was off the bike was the right thing to do. I would like to find out who the manufacturer of the Ampedbikes Stealthy motor is, and I would also like to know how to open this one up and if its possible to repair. Should I be trying to coax the hub to roll backward from the axle?
 
You're just confusing everybody with the information you give and the tests you do.

Put the motor back in the fork. With it disconnected from the controller, turn it by hand in each direction. It should turn freely in the forward direction. You should feel some resistance in the backwards direction. If it's difficult to turn backwards, there's a short in the motor wire.

If everything is normal in that test, Connect it to the controller without switching it on. If you can feel much more resistance to turn it backwards, there's a short in the controller.

If everything is still normal in that test, you have incorrect connection sequence, damaged hall wire or faulty connection between the motor and the controller. Note that the motor connector needs to go all the way to the guide-line.
 
Post some pictures. I agree with the others. Either shorted phase wires in the motor or a busted clutch if it is a gear drive. Also, make sure you have the wheel oriented in the proper direction. It is easy to mount a front hub motor wheel backwards if you do not know what you are doing and it does not have a disc.
 
Thanx for the response. I'm going to run the tests tomorrow when I'm off work. I will report back soon.
 
It's been a long week folks but I was able to get some bike repair time in. I really want to get some biking time in tho! I performed the tests suggested earlier here. I completely disconnected the motor cable from the controller, no batteries, nothing. Turned the bike upside down and the same problem. The rear wheel with the hub motor would turn freely in the forward direction but was totally frozen turning backwards by hand. After about 20-30 minutes of gentle coaxing, I was able to get the wheel to roll backwards with some light resistance. I think may have been something in the gears inside the motor but I am not sure. Next, I plugged the motor cable back into the controller without the battery connected. No difference. Next I flipped the bike over, right side up and connected the battery. Switched on the controller and power switch under the throttle and got full power to the throttle, but the motor still wont turn, twitch or even make a sound. I did not test it long enough for the controller, motor or cable to get warm.
I would like to know if there is a way to test the motor without the controller? Has anyone here ever opened up a an Ampedbikes Stealthy motor? Will hub motors run with the brake electronics disconnected? (another test to run) Does anyone have a working Ampedbikes Steathy or other 36volt motor and or controller on a 700c wheel available? Thank You so much!
 
Trying to run your bike with a faulty motor will blow the mosfets in the controller. When you found that your motor was jammed, there was no need to do any further tests. Clearly something is wrong. The symptoms would indicate a short between the phase wires, though it could be that the gears in the motor are broken/rusty.

Your motor is a MXUS XF07. I'm pretty sure that the clutch is between the gears and the motor rotor, so the gears turn when the wheel free-wheels. That would imply that your gears are OK, so the short is in the wire or in the motor windings. If you changed the resistance by fiddling with it, it implies that you have an intermittent short, which would be the wires.

Look again at the motor wire where it comes out of the motor. Is there any damage?

http://www.mxusebikekit.com/admin/upimg/20111022143048119.jpg
 
Does sound like the clutch or gears need replacing. I was thinking it was the motor or controller fried.

I'd just get a new motor entirely, that amped geared motor was tiny, not really all that great a motor. Fine if you want to build the lightest possible bike, but it ran with too much power, or weight, or both.

A bigger motor should run on the same controller, assuming it's not fried too. You have a 22 amps controller btw.
 
Thanx for the replies! Doesn't seem to be any damage to the jacket of the cable going into the motor. The sprocket and chain were pretty rusty when I got it. The problem with it not rotating backward felt mechanical to me. After looking at pics of the inside of the MXUS XF-07 (08?) I am thinking the motor may have been stuck or needs some lube, and maybe I fried the controller sending juice to it when it was jammed?? I have a volt meter. Is there a way to test and determine if the controller and/or motor is fried? I could just order a new controller but to find the exact one will be difficult. Can I just order any 350W 22A controller? Thanx
 
Just to make things clear/ I thought you said that the motor couldn't be turned backwards when it was disconnected. That means a motor fault, not a controller fault. Until you fix the motor, you won't know if the controller is OK.

Let's go through it again. You put the motor in the frame, but don't connect the motor wire.
Spin it in the forward direction. If it spins freely, there's nothing wrong with the gears (probably).
Turn it backwards. It should turn, but not so freely. You should feel a sort of buzzing as each magnet goes past each coi, which happens about 300 times for each revolution of the wheel. If it's difficult to turn, there's a short between the motor wires somewhere. It will feel like something is jamming the gears. If you push hard, it will still turn, but very rough and sticky.
 
Hi d8veh, The wheel wouldn't go backward at all, connected or disconnected. With it disconnected, I gently kept coaxing it backward by hand. After a it began to click and would get stuck slightly while pushing forward, and then it starting to squeak a litlle and had a little more play until finally it turned backward a few inches. I coaxed it some more and it went all the way around backward and did't get stuck at all forward. Now it will turn backward by hard but not as easily as it does forward. Very similar to the youtube video I posted earlier. Still seems to have a bit of a rough spot while turning backward but not much.I thought when I fired it up after that it would work but it didn't.
Just want to say Thanx for all your help on the forum. I've been biking my entire life and really want to get out on the new bike. After that, maybe I can get the US Pro Sport ready for the Mrs!
 
Let's go through it again. You put the motor in the frame, but don't connect the motor wire.
Spin it in the forward direction. If it spins freely, there's nothing wrong with the gears (probably). What's the result of this test?
Turn it backwards. It should turn, but not so freely. You should feel a sort of buzzing as each magnet goes past each coil, which happens about 300 times for each revolution of the wheel. If it's difficult to turn, there's a short between the motor wires somewhere. It will feel like something is jamming the gears. If you push hard, it will still turn, but very rough and sticky. What's the result of this test?
 
Take the motor apart and see what is jamming it up
 
Take the motor apart and see what is jamming it up

...and how would you do that? Have you ever disassembled a MXUS XF07?

No never, and do not have a clue what the MXUS xF07 looks like, until I googled a picture of it and saw it's assembly, and I assume someone somewhere assembled it, do an "unassemble". Since this thread has gone on for an angonizing 10 days over a fix (or discovery what is wrong) that should take a couple of hours. I made the suggestion to "take it apart".

francis
 
spdas said:
Take the motor apart and see what is jamming it up

...and how would you do that? Have you ever disassembled a MXUS XF07?

No never, and do not have a clue what the MXUS xF07 looks like, until I googled a picture of it and saw it's assembly, and I assume someone somewhere assembled it, do an "unassemble". Since this thread has gone on for an angonizing 10 days over a fix (or discovery what is wrong) that should take a couple of hours. I made the suggestion to "take it apart".

francis

It has a screw-on side that requires a special tool to unscrew it. Even if you get/make the special tool, these side-plates are very difficult to unscrew if the motor has been used for any length of time.
 
You don't have to replace it with the same motor. You can get any of the similar motors from BMSBattery, Greenbikekit, Elifebike or sellers on Aliexpress for about $100.

http://www.aliexpress.com/item/36V-48V-250W-High-Speed-Brushless-Gear-Hub-Motor-E-bike-Motor-Rear-Wheel-Drive-MXUS/1880934447.html?spm=2114.40010208.4.15.FKDl7A
 
Thank you, I will check out some of those motors. No since getting a whole new kit. I might also try to take apart my motor as soon as I can get a break from work.
 
To get it apart without special tools, insert the head of a 5mm cap head screw (Allen screw) in one of the dimples. It will be a nice snug fit, leaving just enough head exposed to hit. Use a hot air gun to heat up the hub in the area between the spokes until it's just about too hot to touch. Smash the screw tangentially in the anti-clockwise direction using a hammer and screw-driver or other suitable drift. After a few blows the hole enlarges, so the screw doesn't fit so well, in which case, move the screw to the next hole. Draw a pencil line over the join, which is near the spokes. That will show you if anything is happening. When the lines are about an inch apart, you should be able to unscrew it by hand.

You'll end up with a lot of screwdriver marks on your motor and slightly damaged dimple, but at least you'll have your motor apart. You can re-tighten by hand because the force of the chain will fully tighten it as soon as you start riding again.
 
Back
Top