sooo, my tension is loose and i tighten it, next thing you know, the chain is binding and making an ugly noise. The chain is brand new and i don't know how old the cog is, but assume it's in pretty new condition... i loosened it back up and it's not binding, but it is loose, too loose. Also my chain can come off and that's not good when my track fork is back on and i'm riding brakeless. what to do?