Clicking noise coming from cog on fixed gear Ever since I put my rear wheel on after taking it off, I have had this constant clicking noise from the cog. 

Here's what I know:


It wasn't always like this. I rode for a few months with no clicking noise.
Chain line appears to be straight.
Clicking sound comes from the top of the cog when pedaling forward and the bottom of the cog when pedaling backward.
Chain appears to "bounce" quite a bit when leaving the top part of the cog when pedaling forward and when leaving the bottom part when pedaling backward.
Is it the same link every time? There could be a tight/sticky link in the chain from when it was installed. I'm not sure why that would have come up after removing/replacing the wheel, but it's worth checking. 


Mark or otherwise make note the problem link
Take the wheel off or push it in the dropout to put slack in the
chain
See if that link is difficult to bend
If it is difficult to bend, then set your thumbs on it, push it side-to-side, quite
    firmly but not with all your might, until it becomes less sticky