Re: Chain keeps breaking?
There are three things I will suggest...
First, bevel the sides of the sprocket teeth with a grinder or file so that the sprocket feeds into the chain without snagging it.
Second make sure the sprocket spins as perfectly straight as possible!!
Third, make sure the chain tensioner is feeding the chain straight down onto the sprocket, & then screw the tensioner into the frame so it doesn't move!