I have two and they spin backwards when you try to stop, no coaster brake. I took one apart and found there is a steel wedge in there that looks like it was cut from pipe. I think this wedge moves and is either the brake shoe or it moves and pushes the brake shoes apart. This wedge was polished from friction on it’s top so I guessed it was worn out. I spent an hour trying to make one from old bike tubing but it was either too thin or too thick. I tried grinding and filing down one that was too thick but never got it right. The curve of the tubing was off a small amount. Finally I made a tape pattern and cut a shim from a piece of aluminum flashing. It now spins forward and engages the brake when you turn the cog backwards by hand, which it didn’t do before. I laced it to a 26 x 1 3/8 rim, as I had spokes that fit. It’s a skip tooth cog so I’ll someday put it on a skip tooth bike to see if it works. I don’t want to take off fenders and play with chain adjustment on one of my built bikes so I’ll have to wait to test beat it. Anyone ever had success trying this?