Power assist not working all the time ITS FIXED !

[jangles]

So I have a Fat bike with a Bafang hub drive . Today I went for a ride and something is off . It seems like it's only firing pedal assist about half time around . It works fine on all levels of throttle but it goofs about half time in all levels of assist . Any thoughts on this ? TIA

 

[dogman dan]

Look first, always, for a connector problem. Start at the battery, work your way through from there.


But always works throttle, but not on pedal assist, look for a problem with the wires to the pedals

 

[docw009]

Look also at the bracket for the pedal assist sensor and the magnetic disk. Some owners report the disk getting loose somehow and slipping on the crank axle, or it has moved too far from the sensor.

You also mention a BTN model with two motors. Is that the one that is acting up?

 

[jangles]

I just changed the title a little . The PAS does work but only about a half of a pedal stroke and then it cuts off then on the other side it may kick in but very briefly . I thought that might be normal at first but I switched to my wifes bike and tried it and hers work really good . The bracket with the magnets is tight and I see nothing in the wiring from the battery that looks abnormal . TIA

 

[jangles]

Look also at the bracket for the pedal assist sensor and the magnetic disk. Some owners report the disk getting loose somehow and slipping on the crank axle, or it has moved too far from the sensor.

You also mention a BTN model with two motors. Is that the one that is acting up?

Yes it is the BTN or Eunorau AWD Fat .

 

[docw009]

There's got to be two controllers for the two motors. I would guess they use PAS for one motor, and throttle for both or one motor?

With the above complexity, you probaly have to figure out which motors are supposed to be running under these inputs and then you can say throttle good, PAS bad, or whatever.

 

[jangles]

No , it has one controller split to separate motors and a rocker switch to engage the front motor or the back motor or both motors . The PAS acts up in all the modes and throttle runs perfect in all modes .

 

[Paderolis]

I just changed the title a little . The PAS does work but only about a half of a pedal stroke and then it cuts off then on the other side it may kick in but very briefly . I thought that might be normal at first but I switched to my wifes bike and tried it and hers work really good . The bracket with the magnets is tight and I see nothing in the wiring from the battery that looks abnormal . TIA

Could the PAS disc be warped somehow? Maybe some of the magnets aren't lining up well with the PAS sensor during rotation.

 

[jangles]

Thanks for the suggestions guys . I appreciate it .

IT was A broken CONNECTION in the ROCKER switch !!!!!

 

[dogman dan]

Anything intermittent, its 99% certain there is a bad connection somewhere. With your type plugs, a lot less frequent, but sometimes those things still have a loose connection, inside all that molded plastic. It can sometimes mean replacing the whole wiring harness, with those sealed plugs.

 

[docw009]

Pretty cool. I see two motor cables coming out of your controller. They have to be independent of each other, so it's like two controllers but in the same box and sharing the same throttle and PAS.

That's something most of us have not seen before.

 

[jangles]

Pretty cool. I see two motor cables coming out of your controller. They have to be independent of each other, so it's like two controllers but in the same box and sharing the same throttle and PAS.

That's something most of us have not seen before.

Yeah , I havent seen it either . I'ts tucked in the frame by the battery somehow . I'm sure glad I didnt have to go any deeper . Now I can get back to my Cruiser build !

 

[amberwolf]

Crystalyte actually had a controller with two phase wire sets, and a toggle switch between htem. IIRC it was for a motor with two sets of windings (though I don't recall if it was just to get different speeds, or what).

They also had a controller with two phase *and hall* wire sets, which actually powered two separate motors, for a 2WD system, and a common throttle / brake between them. INside the box were two independent controllers.


I have one of each of those (non-working ) in my controller-parts box....