I’m in the process of my first build with a conversion kit. Its a front hub motor and when I first got it all hooked up something wasn’t right. With the bike on blocks I pushed the throttle and the motor shuttered a bit. I let off the throttle checked all the wiring and tested it again. Sadly I had the same problem, quick shutter then nothing. This time however I got a bit of smoke from the 9 pin connector.

I finally did get the motor to work but I still have issues. It’ll run fine for a while but sometimes I loose all power and other times just get that same shutter and nothing else. I have found that disconnecting and reconnecting that 9pin connection will remedy the problem but sometimes I have to do it two or three times.

Does anyone know why this is happening, if it is a problem with that 9 pin connector, and if so what so what I need to do to fix it??? Any help would be greatly appreciated. I’ll attach a picture of the female end of the connector where you can see the damage.

There's a line on the connector that shows how far in you must push it. They're quite tight, so people often stop short of the line thinking it's enough, but it isn't.

 

Before I can say anything more than that you'd need to do some tests. Unfortunately to do any testing, you need access to the wires, which you can't get with moulded connectors. I always use spare ones cut off defective motors and controllers for testing. Is your motor cable with the female 9 pin connector attached to the controller or does it have a block connector and bullets at the controller end?

Edited December 5, 20196 yr by vfr400

With those connectors you have to make sure that it is inserted all the way up to the line. There is the alignement arrow but also an insertion indicator line.

It looks like there is some indication of poor connection on the pin that is at the 7 0'clock position in your photo, if this is a phase wire, poor/resistive connection will give you this. You could always try some silicon spray to help you put it together.

As a last resort you couold always cut the connectors off and hard wire/solder the connection - make sure the powers off first.

 

ps Crossed with Vfr's post

Ben is correct a close up view of the female 9 pin Julet shows arcing/burning on one of the phases and possibly two of the hall lines. The male connector may have been lined up incorrectly or not pushed firmly to the line, a bent pin/s may be the cause.