Quote Originally Posted by DebW
If the front derailleur needs adjusting, it's usually a scraping sound, not a clicking sound. Is the sound still present when you turn the crank by hand (on a work stand or with the bike upside down), or only under riding load? If the sound is there with the bike stationary, look to see if the chain is scraping the front derailleur or something else. If the rear derailleur is out of adjustment, the chain could be ticking a second sprocket. Another possibility is that the chain and or cogs are worn and need to be replaced. If the sound occurs on the cogs that your ride the most and the drivetrain is more than a couple years old, this is possible. Your LBS can quickly check chainwear or you can buy a chainchecker. Also, some people on this board have mentioned that using WhiteLightning lube on the chain has lead to drivetrain noise.
Thanks DebW. It is a clicking and not scraping. At least I think it is. Yup the sound is still there when I hand crank it. I will take a closer look tonight. I think my chain should be okay as I replaced it about 2 months ago. It's just aggravating to listen to and to avoid it, I end up having to mash up hills!