Mating an 8-pin motor to 6-pin controller?

[shackmech]

Hi,
I recently purchased an "ikea folkvänlig" with a water damaged motor ( "HD 8FUN") and since I have another complete wheel with a working motor from an ecoride ("BF1404D18378") I hope it's possible to switch them. However, the HD 8FUN is a 6-pin motor and the other one is 8-pin...

Apart from the three phase pins, how should I connect the rest? I understand there are hall sensors and stuff (for a smoother start?) - but are those really needed?

 

[docw009]

I believe 6 pin motors don't have Hall sensors. There's the three phase wires, plus +5V power, ground, and signal for a speed sensor. You run these motors with sensorless controllers.

The eight pin would be three phase wires, three Hall sensor outputs, +5V power and ground. Often a 9th pin is added to support a speed sensor.

It sounds like you want to use the 8 pin motor with the bike that has the water damaged 6 pin motor? I think that will work, as a sensorless controller should run it. Connect the three heavy wires which are the phases. You might need to hook up an external speed sensor if the controller stops. Anyway, I've got a 9 pin motor hooked up to a sensorless controller and it runs fine.

 

[shackmech]

I've got a 9 pin motor hooked up to a sensorless controller and it runs fine.

Thank's, that gives me some hope! Yes, you've understood correct - I'm cheap and I wanna fix it what the parts I already have lying around
Where can I get an external speed sensor? Perhaps are there any other parts I can cannibalize instead; like the sensor from the pedals on another ebike or an industrial NPN-sensor?

 

[docw009]

See if it works first. That bike with the sensorless controller, I am using a pedal assist sensor mounted on the rear wheel. It will work without a speed sensor but then I don't see the speed when coasting.