Thought the BB was bad; was the chain
 

Just a couple weeks out using my new bike (sig) it developed a fine grinding sound like bad bearings emanating from the BB. Quite noticeable and annoying on a quiet ride. Today on a whim I sprayed the chain with WD-40 which completely eliminated the noise. I couldn't believe it. I'm not sure how the chain got dry in such a short period, but sure am happy it wasn't the BB. Odd, as when I first got it the cassette and chain seemed awfully heavy with lube. So just a tip for what it's worth.

Oops, wrong forum. Sorry...

:popcorn

Yep, we're probably in for a long one. Another use for WD-40.

I suspect it was the chain's rollers, which, while they don't really squeek, tend to rattle from the vibratiions of the tooth engagements at either end of the tensed upper run of the chain. It really can make an odd, if subtle, racket, which is instantly cured by even the lightest of lubes.

Don't expect the WD40 to damp out the roller's vibrations for long though, that's a job for a slightly more-substantial lubricant.
With luck, the WD40 might actually re-hydrate and re-distribute some of any dried lube within the chain, but I wouldn't count on it and would measure the chain for it's "elongation wear" at this time.