Motor Replacement Question - Ridstar Q20

[Namikis]

I have The original motor of a bike out - see picture.



The harness is damaged, so I found a possible replacement on eBay and bought it. The plugs are not identical, see existing motor pinout:



The new motor has an extra wire using a slightly different pin configuration, but the rest of the motor looks almost identical net of the board:





Can I replace the plug of the new motor with the one from the old one, mapping the wires by color? Alternatively, are there schematics available anywhere so I can figure out what each wire is doing based on the plug layout? Thanks in advance!

Nam

 

[Namikis]

The bike is a Ridstar Q20, if that helps.

 

[HumanPerson]

Welcome to the forums

 

[Annieolnie]

I'm sorry, you can't really believe in any color coding with Chinese ebike motors. Could you tell me what exact motor you bought. I've never seen that plug before and it has a pin for an extra function (it might be for temperature). The 3 large pins are your phase wires and you can test them from the motors board for continuity. Do these motors have the same wattage? Your Ridstar has a 1500w motor? I've been trying to find your original plug to look for a pinout but so far no luck. The red color worries me as that is usually for higher wattage and I haven't yet found it. You should be able to move your old plug, but getting the hall sensor wires right could be tricky. Have you watched some videos on installing a new motor cable? That would show you some of people's techniques, meanwhile I'll look around a bit more for the pinout.

 

[Annieolnie]

So, there is a video on YouTube from "Ridstar Gunna" for changing out a ridstar motor. I personally would not let this kid change a pair of socks, never mind a motor, but the interesting thing is that his old motor had a stock 9 pin connector and the new one they sent had the red plug 9 pin, that you show, so theoretically they should be interchangeable. I will put the diagram for that pinout here. You should test this all out with a multimeter. You can put a pin in your controller plug and test for ground and 5 volt ref. etc. Remember the female plug will be a mirror image of the male, you need to stay oriented to the plugs arrow and don't desolder or cut anything until you have both boards figured out. I can't find that other plug anywhere. Who makes that motor? Let us know how it is going and good luck.

 

[Namikis]

So, there is a video on YouTube from "Ridstar Gunna" for changing out a ridstar motor. I personally would not let this kid change a pair of socks, never mind a motor, but the interesting thing is that his old motor had a stock 9 pin connector and the new one they sent had the red plug 9 pin, that you show, so theoretically they should be interchangeable. I will put the diagram for that pinout here. You should test this all out with a multimeter. You can put a pin in your controller plug and test for ground and 5 volt ref. etc. Remember the female plug will be a mirror image of the male, you need to stay oriented to the plugs arrow and don't desolder or cut anything until you have both boards figured out. I can't find that other plug anywhere. Who makes that motor? Let us know how it is going and good luck.View attachment 20335

This is very helpful - thanks for digging it up. Will watch the video as well and report back when I am done.

 

[Namikis]

A quick update on this project: the 10 pin plug was really a 9 pin in disguise - the 10th pin was not connected to any wires. I will test the new motor later this week and rport back. I matched the wire colors exactly.

 

[Annieolnie]

Did you test for continuity? In China, color coding isn't even a concept. You might as well have color blind puppies choosing your wiring.

 

[Namikis]

Well - voila - it appears the Chinese respected the color coding in this case! The bike is working great! Thanks for the help!

 

[BiggKidd]

Well - voila - it appears the Chinese respected the color coding in this case! The bike is working great! Thanks for the help!

Just curious how many miles you had on your bike? From the damage it sounds like the wheel was a bit loose at the mount is that correct?

 

[Archiebunker]

Just curious how many miles you had on your bike? From the damage it sounds like the wheel was a bit loose at the mount is that correct?

Just curious how many miles you had on your bike? From the damage it sounds like the wheel was a bit loose at the mount is that correct?

Well - voila - it appears the Chinese respected the color coding in this case! The bike is working great! Thanks for the help!

Do you have a link to the motor you purchased?

I’m in the same boat and they seem to be sold out everywhere I can find thanks in advance

 

[Annieolnie]

I’m in the same boat and they seem to be sold out everywhere I can find thanks in advance

Hi, I was going over this thread and I thought I'd let you know. I picked up a portola rear wheel with a 750w hub motor for a different project of mine. The wheel is beautiful. It came through with the same red plug as the original Q20 above top, which has me scrambling for an adapter, but would be fine for you. It arrived with rim tape and a freewheel on it, which I didn't expect. Ride1up makes a very nice motor. The only thing to consider is that the rim is set for a 3 inch tire, which is what the Portola uses.They even offered free shipping. If you Google Ride1up parts, that section of their website should come up.

 

[Victor Dupont]

Well - voila - it appears the Chinese respected the color coding in this case! The bike is working great! Thanks for the help!

Hi!

I am no expert at all, but just wanted to share something I learned, it case it spares you some big trouble.

I learned that when mapping a motor to a controller, and trying to figure out which phase wire goes to which phase wire and which hall sensor wire goes to which hall sensor wire, not only do the colors mean absolutely nothing, BUT ALSO, there are combinations in which the motor is running but overheating. And if you ride your bike in such a configuration, you'll burn your motor.

Apparently the way to check is to measure amperage on the phase wires while testing it slowly.

I never found a way to do that exactly, but I guess at least you can make the motor run slowly by putting the bike upside down, and check that it's not heating.

Hope it helps