Oh, no, What did i do? I oiled my pedal assist sensors.

Robbie_D

Member
As i mentioned several times, i doubt the sensor got moved away from the magnet wheel. I posted pics of the brace that supports the sensor. It doesn't look like it has been bent. I was only oiling the chain, so nothing moved the sensor. As i mentioned before, it's really rigid in place, the thing does not move.
 

Robbie_D

Member
That gap is about 8mm. It need to be 1.5 to 2mm. In the States we use a nickel. A nickel is 2mm thick.
I just measured it. It's 12 mm away from the magnet wheel.
Geez, i dunno. Nothing banged the bike overnight as it sat in front of my apartment door, unless my janitor did something to my bike. But why that and why then (such a coincidence after i just oiled the sensors). Did you see the pics of the sensor brace?...it looks straight to me. I reposted the pic here for you.
 

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PedalUma

Well-Known Member
Region
USA
Use your thumbs. Try first moving the magnet ring out, to within 2mm of the sensor. Magnets work at the square of the distance. At 12 mm it does nothing. If it does not budge than bend the sensor to within 2mm of the magnet wheel. What happened is oil got onto the crank arm bb shaft and the magnetic ring slid out of position.
 

rtp

Active Member
Region
USA
As i mentioned several times, i doubt the sensor got moved away from the magnet wheel. I posted pics of the brace that supports the sensor. It doesn't look like it has been bent. I was only oiling the chain, so nothing moved the sensor. As i mentioned before, it's really rigid in place, the thing does not move.
Yet no light, so something’s not working. You can keep saying nothing happened, but something did. No light = replace the sensor, or take it apart and contact spray clean it, or try the free option and move the sensor as Uma’s saying until/to see if you can get it to light up…. only so many choices her and we’re trying to help..
 

Robbie_D

Member
Ok, it's a bafang hub-drive motor. Your pic of the speed sensor doesn't look like a Bafang mid-drive sensor. This is a typical Bafang motor mid-drive sensor. Might have to do some searching on greenbike or maybe post a pic of the other cable end etc. unless someone can confirm a different sensor part..
This DYAD bike company...i am not so sure about.
Use your thumbs. Try first moving the magnet ring out, to within 2mm of the sensor. Magnets work at the square of the distance. At 12 mm it does nothing. If it does not budge than bend the sensor to within 2mm of the magnet wheel. What happened is oil got onto the crank arm bb shaft and the magnetic ring slid out of position.

Ohhhhh. i just did what you said and the magnet wheel moved. I moved it closer to the sensor. Wow. It WORKS.

I am SO grateful for that. Thank you! Thank you. Thank you!
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
The "no light" issue is a "no power" problem. It's not working because there is likely some kind of a wiring issue. First place to look would be at the connection closest to the sensor, most easily found by following the wire from the sensor. Make sure it's plugged in tightly. If it still doesn't work, pull the connector apart and check for corrosion.
 

Robbie_D

Member
Use your thumbs. Try first moving the magnet ring out, to within 2mm of the sensor. Magnets work at the square of the distance. At 12 mm it does nothing. If it does not budge than bend the sensor to within 2mm of the magnet wheel. What happened is oil got onto the crank arm bb shaft and the magnetic ring slid out of position.
Yes, this fixed it. Thank you so much.

Should i move the magnet wheel back and forth enough so i can take a Q-tip to remove whatever oil is there, in case it slips again?
 

Robbie_D

Member
The "no light" issue is a "no power" problem. It's not working because there is likely some kind of a wiring issue. First place to look would be at the connection closest to the sensor, most easily found by following the wire from the sensor. Make sure it's plugged in tightly. If it still doesn't work, pull the connector apart and check for corrosion.
It's fixed now. The magnet wheel moved too far away from the sensor.
 

Robbie_D

Member

Pedaluma. Yes, this fixed it. Thank you so much. I moved the magnet wheel closer to the sensor. The sensor itself is too rigid to move. The problem was the magnet wheel.

Should i move the magnet wheel back and forth enough so i can take a Q-tip to remove whatever oil is there, in case it slips again?
 

Robbie_D

Member
Yet no light, so something’s not working. You can keep saying nothing happened, but something did. No light = replace the sensor, or take it apart and contact spray clean it, or try the free option and move the sensor as Uma’s saying until/to see if you can get it to light up…. only so many choices her and we’re trying to help..
I said nothing happened to the sensor which is rigidly in place and does not move. I appreciate all the help rtp, believe me, please. Sometimes in forums, the same question gets repeated and so the same answer keeps coming. Uma's suggestion fixed it 100%.
 

rich c

Well-Known Member
Late to the discussion, but thought I'd add a couple things. Brake cleaner is acetone. Acetone will melt certain types of plastic and paint. Denatured alcohol is a much better choice. Also most magnet holders are not rigidly mounted. They usually have little fingers that hold with friction and can be easily slide back and forth to set the fit to the sensor.
 
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chunk

Active Member
Region
USA
Yes, late to the party too, but for others, always look and see that any spray cleaner says clearly that it is plastic safe, if it will come in contact with any plastic. Most contact cleaners these days are plastic safe, such as the CRC mention in other posts. Also contact cleaners are usually zero residue formulas, after they dry, they leave nothing behind.
 

JES2020

Well-Known Member
Should i move the magnet wheel back and forth enough so i can take a Q-tip to remove whatever oil is there, in case it slips again?
I didn't see a response to your question, so here are my 2 cents.
Sounds like you need to sure up the magnet wheel, it should not be easy to slid on the crank.
I used epoxy putty to stabilize the grip of the magnet wheel to the crank on a loose magnet wheel, it works perfectly.