Disc brake clicking noise I just took my rear tire off of my mountain bike that has hydraulic disc brakes (elixer5). When I put the wheel back on and started pedaling it made a clicking sound.

At first I thought it was the spokes rubbing up against something (that's what it sounded like, some metal sound). I took the tire off again and took a good look at the disc brake pads, I saw a skinny metal "r" shaped thingy leaning out in the slot where the disc would fit. 

Is this where the clicking is coming from and if so how do I fix it? Please ask for any more information I couldn't think of for more clarification.
The metal "R" shaped piece is likely the brake return spring (#7,8 in the image below):



If it is visible as you describe, you are likely missing a brake pad, and the spring is contacting your rotor.

You will need to find or replace the pad to fix the issue.