Conversion Kit Cassette Question


New Member
I have been installing a BAFANG 48V 500W conversion kit and have reached a point where the instructional video shows a completely different piece than has been provided. Is there a piece I need to buy or a different method of installation I am missing?

The first image shows the main line coming out from the hub of the bike, completely clear of anything on it, the second image shows the part he introduces to hold the cassette in place, and the third image is what my set looked like out of the box.


  • IMG_5009.jpg
    560.6 KB · Views: 178
  • IMG_5008.jpg
    196 KB · Views: 167
  • Screen Shot 2022-07-18 at 4.26.17 PM.png
    Screen Shot 2022-07-18 at 4.26.17 PM.png
    4.3 MB · Views: 165
My bet is that first picture has the nut and washers slid to the end of the wire, where the electical connector is....
My bet is that first picture has the nut and washers slid to the end of the wire, where the electical connector is....
Even if that was right, the nut doesn't fit the bolt, it screws down a little then gets stuck.
You may have mis match thread pattern just a guess. If so, you need a new nut to match the bolt or whatever it is you are trying to fasten with the nut.
The only problem is this plug prevents me from taking them off.


  • Screen Shot 2022-07-19 at 2.00.51 PM.png
    Screen Shot 2022-07-19 at 2.00.51 PM.png
    30.8 KB · Views: 134
Did you try putting a wrench to it ?
What I would do is wrench it in nice and slow when it gets stuck, back off squirt wd 40 and repeat the process.
Looks to me the nut came with the kit. It should fit.
I'll try, thanks.
Your third photo is of a lock ring cassette. Do you have a screw-on freewheel tool? Or a free-hub cassette tool? If you have the wrong one, that is the problem. Next, I have worked on a lot of bikes. Nuts and washers always fit over the connector. If it does not, than that is a defective product. Send it back.

Last edited:
Probably not, I had to do some cutting to make a PAS sensor plate fit onto the bottom bracket.
Actually, I've found that axle nut rarely big enough to clear that connector on the end of the wire. If you need to replace/remove that nut, you'll be removing the wiring connector. Think about it. That's going to be one giant size axle to use a nut that will slip over the wiring connector.

That adapter in the middle pic? Most of those don't fit over that axle nut either. Generally, one has to cut a slot the length of that adapter so you can slide it over the wire to use....
Most hubs are use a 12mm diameter axle, with two sides flattened to 10mm, This allows the axle to fit into the dropout slot, which is 10mm, but the nuts and washers are 12mm,

The standard nine pin Z910 Bafang plug for 500W motors is slightly less than 12 mm in diameter, so it will fit thru the washers and nut supplied for the hub motor. When you get into the Bafang motors rated for 750W, they use a bigger diameter Z916 connector which won't fit thru a 12mm washer or nut. The Z916 also has an octagonal shape at one end.

There's no need to use a tool to screw in a freewheel. It will tighten naturally in use, and a took is needed to remove it.
You might check eBay or Amazon for a quick domestic supplier of the identical pickup.
This one is a free hub cassette with a lock ring.


  • 1658266111973.png
    425.3 KB · Views: 146
While looking at the wheel again, I thought about how to prevent the cassette from sliding off while riding, then I had an epiphany! The nut doesn't go down all the way because that gap is where it fits into the rear dropout in between the two washers. Thank you all so much for your help, couldn't have done it without y'all!


  • IMG_5021.jpg
    396.4 KB · Views: 143