Two 750 watt hubmotors both dead

Hi,

I have two quite new Lunacycle 750 watt hub motors both running on 52V, only had a handful of rides on em.
Now they both seem dead, display turn on just for a second before turning off. I dont see any error on display.
The batteries are tested and fully charged.
Any ideas?

Heres a link to the product:

https://lunacycle.com/geared-hub-ebike-kit-750w-for-front-or-rear/

Internal gears don't last forever. In fact usually the first thing to fail.

For what you paid for those, I'd contact the vendor.

I doubt there's anything wrong with the motors. The symptoms you describe are similar to issues I had with my Bafang BBS02. Ultimately, the problem was poor contact between the terminals on the underside of the battery and those on the frame cradle.

This was the procedure that brought my bike back to life:
https://electricbike.com/forum/forum/knowledge-base/batteries-aa/12542-luna-hardcase-battery-documentation?p=37852#post37852

If that's not the problem with yours, at least it won't do any harm to try it out.

Thanks guys, did some more investigating and managed to get life in one of them again, probably bad connection somewhere.

The other one though has broken gears most likely, disturbing sound from motor, plus not running at full speed. :/

Actually I noticed one of the motors sounded weird from the beginning but it was running fine, until now.
Anyone know if its possible to replace gears on motors like this?

Wow, that has got to be the most massive ripoff in the history of the earth.

martianbike said:

The other one though has broken gears most likely, disturbing sound from motor, plus not running at full speed. :/

Click to expand...

That sounds like a Hall sensor problem (which could in turn be a Hall sensor wire or plug problem).

My guess with the limited info given is that all the problems are from poor connections (broken wires, bad crimps, oxidized contacts, loose contacts backing out of housings only when plugged in, etc).

90% of problems are the wires. Particularly vulnerable on that kind of kit is the tiny contacts to the display and throttle, followed by the motor wires. The motors are fine, but you ran them with some bad contacts causing them to stutter and run slow.

Display going dark could be the battery connection, so always start your inspection there. How do you know the battery is charged? It could always be the battery is the problem.

Betcha you got some bent pins on those plugs to the display, or perhaps just a simple defect on a part of the harness. Look really close at those plugs. If you ever plugged in without the arrows or keyway lined up, you might have wrecked the plug.

Does he sell parts? Used to be he did not. If the pins look good, you might just have a bad harness wire.

Got a fellow codger today! On secong controller both do th3 same rhing intermittent cutout. He insist# o; buying another controler an$ that since h3 rides o; flats i5 couldnt be a connection or a battery qterminal. What do you do?
But intermittent cutouts with no error code on bbsxx is nearly always wiring, or connecrions, IME.