Vevor 72v Razor Build help

[Alex_Q]

So I recently got given a project and it won’t run so I need some help!

The bikes electrical components are a vevor 72v 3000w controller and motor and a hot paxx 180a battery.

The problem is that the motor runs for a split second right after the bike is turned on, the motor then stops suddenly and something starts whining when the throttle is used, when the bike it turned on and off after this no sound or voltage draw occurs. When the bike is doing the whining noise the voltage is dropping and the motor wires are getting warm. Controller connector and battery made a spark/pop when connected which I think is normal. Voltage meter turns on when key is turned so I don’t think it’s the electrical lock. Could it be that the controller goes into protection mode when the throttle is applied because of to high of a current?


The guy who gave it to me said that he tried a different throttle and motor before which both supposedly worked. I just got a new controller that I know works which does not make the bike run, it still does the exact same thing as the previous controller. Previous owner said that he was riding around and it began cutting out intermittently and by the time he had got home it was fully cut out. I know that the battery 100% works so it couldn’t be that.


Phase wires were wrapped in electrical tape and have some residue but I don’t think any in the contact point between the motor and controller phase wires. The hall wire connector is next to the phase wires so could this be electrical interference like I saw in another post? The controller also has 2 black connectors which go together to activate self learn but nothing happened when I connected them.

Any and all help is appreciated!!

I’ve attached image of the controller wires

 

[Alex_Q]

I opened up the old controller and I don’t see any damage anywhere so now I’m thinking it might just be the wiring or a problem with the controller protecting itself?

 

[neptronix]

The problem is that the motor runs for a split second right after the bike is turned on, the motor then stops suddenly and something starts whining when the throttle is used, when the bike it turned on and off after this no sound or voltage draw occurs. When the bike is doing the whining noise the voltage is dropping and the motor wires are getting warm.

Sounds like an incorrect phase/hall combination, or a shorted winding inside. Why is there electrical tape over the connectors?

Controller connector and battery made a spark/pop when connected which I think is normal.

That's normal if there is no antispark designed into it. XT90 connectors with antispark could add that.

The guy who gave it to me said that he tried a different throttle and motor before which both supposedly worked. I just got a new controller that I know works which does not make the bike run, it still does the exact same thing as the previous controller. Previous owner said that he was riding around and it began cutting out intermittently and by the time he had got home it was fully cut out. I know that the battery 100% works so it couldn’t be that.

Do you have some kind of display of voltage / wattage / amps to verify the battery is not cutting out and something else is happening?

 

[Alex_Q]

Yeah there is a voltage display which stays on the whole time during all of this

 

[Alex_Q]

I’m pretty sure he just put electrical tape over the connectors to prevent them from touching, I’m assuming it’s the shorter winding your talking about because it ran before with this same phase combination, but at the same time the previous person tried two motors and had the same problem, the other motor had only 3 weeks of use and was working.

 

[Alex_Q]

Update, whenever I turn the motor, it does the quick turn for a split second then stops again

 

[glennb]

Trying a different controller was sensible, but like neptronix suggested, now you need to check the hall and phase wiring.

 

[Alex_Q]

I’ve tried a bunch of phase combinations but no changes to the hall, just found out that when I remove the chain the motor spins when I I get turning for a second so I think it’s the motor.