Mototec Fatboy 48V 500W Scooter issues

Hello All,

I am new to this forum. But I just picked up this Scooter for really cheap and it does not seem to run at all.
Minor issues cosmetically is missing stem/clamp that attaches handlebars to fork and a broken bracket on caliper, but I can fix these.

Issues I have is everything powers on even the headlight, but no movement of the wheel and the 4 batteries are fully charged.
- Does the rear wheel with the hub motor in it suppose to move freely? I can not move it at all and will not budge with any great force.
- The controller is making a high pitch sound (not annoying but there is a sound) when I turn the throttle, is that normal?
- How can I test the controller and/or the hub motor?

Any help is appreciated.

thanks
Matt

Sounds like the Motor is rusted shut. There isn't much you can do unless you like to get your hands dirty.

I managed to remove the stator on a Chinese scooter hub that was seized for 2 years.
I put it in a huge bin with some salt water and did some electrolysis to free the stator (took about 3 days).
Unfortunately, the magnets were about 30% corroded so torque was lacking but worked fine otherwise.

I recommend you open the Motor so we can see what it looks like on the inside.

Ok will do! I am hobby automotive mechanic so electronics is kind of new to me. I will take it apart and see what I can find and report back later on.
thanks
Matt

eee291 said:

Sounds like the Motor is rusted shut. There isn't much you can do unless you like to get your hands dirty.

I managed to remove the stator on a Chinese scooter hub that was seized for 2 years.
I put it in a huge bin with some salt water and did some electrolysis to free the stator (took about 3 days).
Unfortunately, the magnets were about 30% corroded so torque was lacking but worked fine otherwise.

I recommend you open the Motor so we can see what it looks like on the inside.

Click to expand...

Pulled it apart and looks like this. Rusted. I tried brushing it off and seen if it works but doesn't so I'm going to buy tire with wheel hub motor.
Or is this salvageable?

I guess you could try submerging the whole motor in something like this:
https://www.wd40specialist.com/products/rust-remover/

I have no idea how well it would work, to be honest.
But if and when you manage to remove the stator without destroying the magnets you have to keep in mind that the degraded magnets will cause the motor to have less torque and more speed.
Drying the rotor in the oven wouldn't be a bad idea to get all the moisture out of the magnets.
Afterward, I would varnish the magnets with something.

And for 21$/gallon it might be worth a try.
You will have to replace the Hall sensors since they most likely got shorted from the rust.
Most motors use 3 Honeywell SS41 Hall sensors or a similar knockoff sensor.

Shouldn't take more than 15-20 minutes to replace the sensors.

You don't have much to lose by trying it.

If you can separate the rotor from the stator, you can just clean it up as good as you can with a wire brush or scotchbrite, then put some paint on the surfaces that rusted. As long as the bearings are OK and nothing is rubbing, the rest of it should be OK.

You might also want to look at where the wires enter the motor and make sure there's a drip loop or something to prevent water from getting channeled in there.

Just wanted to update this thread. So I bought a new Hub motor for my Scooter and bolted it up and powered it up.
BOOM Wheel is now moving and ready to roll, can't wait to try it out.
Its been raining here for the past few days, should be fun to test this out. Any one know what I can do with the old hub motor/wheel? I don't need it and don't want to play with it.
thanks for everyone's help