eBike conversion kit

dvo

New Member
Hello all,
Need some helps here.

Info:
  • Voilarmart conversion front wheel kit, 36V and 500W
  • Mighty Max F2 batteries, 12V and 12AH each (serial connected)

What happend:
  • When everything connected, I twist the throttle and all I got was the wheel turned about 1 or 2 rounds and stopped. I can feel a little force when the wheel turning but nothing else after that. Turned off then power back on, same thing happens.
I have tested:
  • Wheel/Motor moving freely without noise.
  • 3 batteries fully charged and output around 37-38 volt in total.
  • Indicator on throttle showing full bar.
  • All wires connected correctly according their color codes.
Any idea why this happens? Are batteries not providing enough power or I got a bad kit?

Thanks-
 

harryS

Well-Known Member
Is it this kit? It helps when you link the details of your kit.

When the wheel only spins 1 turn, you have it lifted in the air, not on the ground? One turn of the wheel often means wiring problem to the motor.

These kits generally work. There's a white plastic 2x3 connector coming out of the motor. Sometimes a pin falls out on one side. Check that, and also that the wire colors match on both sides. Sometimes someone installs the pins out of order.
 

dvo

New Member
Harrys, thanks for your response and yes that's the kit. It spins in the air for 1-2 turns. With me sitting on the bike, i just feel a little force impact on the wheel but not enough move forward. Would you think the batteries provide enough push?

 

dvo

New Member
I checked the white connector coming out of motor, its pins seem alright to me, nothing bends or broken. However, i noticed a mismatch: white male connector on the motor side has 5 wires (black/blue/green/yellow/red) but on the female connector which coming out of the controller, there are 6 wires (black/blue/green/yellow/red/WHITE). I am not sure if that even matter. Please take a look at my attached pictures ...
IMG_2926.JPG
IMG_2925.JPG
IMG_2924.JPG
 

harryS

Well-Known Member
That's normal. The white wire supports a speed sensor, It's needed when you have a geared motor, but not needd with a gearless motor like the Voilamart. The wire order looks correct too.

What I or an ebike tech would do in this situation is plug in one of my spare controllers to see if the motor or original controller is at fault..I guess you don't have that luxury.

Does the wheel spin smoothly in either direction by hand, when it's connected, but not powered up?

How did you determine you had 37V? Does the throttle show the voltage?
 

sed6

Active Member
3 12 volt SLA batteries? Is that even a thing anymore? For the $210 you spent on those you'd be better off with a lipo battery. I bet you can return those still. I'm guessing that those weak batteries can't put out enough amps. They are probably 6-10Ah batteries that sag to 10v under load. So 250-300 watts, maybe? Is that enough to get rolling? I dunno, I'm noob still. What if you pedal, then engage the motor, will it work then?
 

dvo

New Member
That's normal. The white wire supports a speed sensor, It's needed when you have a geared motor, but not needd with a gearless motor like the Voilamart. The wire order looks correct too.

What I or an ebike tech would do in this situation is plug in one of my spare controllers to see if the motor or original controller is at fault..I guess you don't have that luxury.

Does the wheel spin smoothly in either direction by hand, when it's connected, but not powered up?

How did you determine you had 37V? Does the throttle show the voltage?

Does the wheel spin smoothly in either direction by hand, when it's connected, but not powered up?
>> Yes, it spins smoothly even when it's connected.

How did you determine you had 37V? Does the throttle show the voltage?
>> 37V coming from the batteries. I didn't know what voltage coming out of the controller and going into the motor though. Can you tell which wires I should connect my digital multi-meter to in order to monitor that?
 

dvo

New Member
3 12 volt SLA batteries? Is that even a thing anymore? For the $210 you spent on those you'd be better off with a lipo battery. I bet you can return those still. I'm guessing that those weak batteries can't put out enough amps. They are probably 6-10Ah batteries that sag to 10v under load. So 250-300 watts, maybe? Is that enough to get rolling? I dunno, I'm noob still. What if you pedal, then engage the motor, will it work then?

Yeah, I have a little hunch with those batteries too but is there anyway I can confirm that. Battery spec shows 12AH each, so I "guess" there is enough force but who knows. When I test the kit, I lift up the front wheel in the air and twist the throttle, so there should be no load.

I did try it during pedaling, same result. I just feel a little force in the wheel and it disappears right away.

As soon as I determine nothing wrong with the motor, I am willing to upgrade the batteries.
 

harryS

Well-Known Member
Good you have a volt meter. Disconnect the pedal sensor and power up the bike. The sensor is a three pin connector. Two wires are power and ground (4.5V) and the third is input. They often use black for ground. So see if you can find a 5V voltage on two of the wires. That will tell you that the controller has turned on.
 

dvo

New Member
Good you have a volt meter. Disconnect the pedal sensor and power up the bike. The sensor is a three pin connector. Two wires are power and ground (4.5V) and the third is input. They often use black for ground. So see if you can find a 5V voltage on two of the wires. That will tell you that the controller has turned on.

The connector coming out of the controller to the PAS sensor has 3 wires black, red, and white. Both combinations black+white and black+red return around 4.1~4.9 volts with PAS sensor unplugged.

So is it safe to say the controller is turned on? if it is, how can monitor the actual voltage going the motor?
 

harryS

Well-Known Member
Controller is on, but motor isn't spinning. Check Hall sensors. Here's one video.

Another video. DIfferent motor, but here he uses a digital meter.
 

harryS

Well-Known Member
I guess it's time to contact Voilamart. Wheel turns slightly with pedals or throttle? The green, yellow, and blue phase bullets are firmly seated, Probably a bad controller.
 

Kayakguy

Member
Was going to ask whether your batteries were connected in series, but I see you did that, so should get 36 volts (actually a bit more).