I think what is going on is that the bracket does not hold and the sprockets do not sit in the chain properly. I make a little video. For some reason when I upload to youtube it shakes like I have parkinsons, but I don’t.
Yes if the mounts aren’t solid, you will have all sorts of problems. Add more
screws and put them in the ends of the slot.
I’ve designed better mounts, but haven’t found a good place to manufacture them
(@bee and I had a half dozen sets made, but that cost us $300, so we need to
find a cheaper place)