bleeding the brakes
Time needed: 15 minutes or so
Next, use an extended 8mm socket to loosen the nut on the bleed nipple. A little bit of brake fluid will start to come out, so slip the end of your plastic tubing on right away.
Here's the fun part. This is easier with a second person, but definitely do-able alone. Finger-tighten the bleed nipple again, so you don't let any air back up into the tube. Squeeze the brake lever a few times, and then hold it in. With the lever held in, loosen the bleed nipple valve again, and watch the fluid come out into the tube. After a few seconds, finger-tighten the valve again, and squeeze the brake lever a few more times. Again, hold the lever in, loosen the bleed nipple valve, wait, close the bleed nipple valve.
If you're completely draining the brake fluid, repeat this relatively monotonous procedure until you're out of fluid (removing the top off of the master cylinder reservoir will speed this along). If you're replacing old fluid with new, simply drain out most of the old fluid. At this point, go over to your other brake caliper, and repeat the entire procedure. Most of the fluid will have already drained out, so you'll probably just have to open and close the bleed nipple valve once or twice.
Again, if you're draining out all of your fluid, keep draining out of that second bleed nipple until nothing more comes out. If you're replacing old fluid with new, open up the master cylinder reservoir, and simply start pouring the new brake fluid in on top of the old stuff. When you see new, clear, fluid coming through the tubing, you know it's gone all the way through. Go back to the first bleed nipple, hook up your tubing, and make sure the new stuff is coming through that brake line as well.
Remove the tubing, close up your bottle of nasty brake fluid (please don't leave it somewhere where it'll spill or animals could get to it), put your master cylinder reservoir cap back on, and use the 8mm socket to tighten up the bleed nipple valves. Don't forget to replace the little rubber caps!
That's it for procdure, but before you close up shop, there's one very important thing you want to make sure of -- that your brakes work. Even though you're seeing fluid come out through the tube, it doesn't mean that the fluid is actually pushing your pistons. After you've tightened everything up, sit on your bike, and just squeeze the brake lever a bunch. You'll be able to tell when the fluid starts to move the piston. Walk the bike slowly forward -- make sure you're not on a decline! -- and try using the front brake to stop the bike. If it doesn't stop, you've probably got an air bubble in the line. Bleed the fluid through a little bit more, and watch the tubing for bubbles. Keep bleeding the fluid until you don't see any. It can get tedious, but you'd much rather be bored while bleeding out air bubbles in your garage than be grabbing your brakes on the road and not have the bike stop. ;)