Originally Posted by
chattahoochie14
but my chain is still going slack when I pedal backwards, and is still not spinning freely. The mechanic said that it was nothing to worry about, but I have my doubts.
Ask your mechanic to try harder. You should certainly be able to stop pedaling and coast. Some will argue that back-pedaling is unimportant, but I disagree.
Possible causes I'm familiar with include a bent derailleur cage, a gunked up freewheel (on older style bikes), and stuck chain links.