Bicycle Mechanics - Time to replace BB?

I'm hearing a clicking noise coming I believe from the BB. I'm almost positive it's not the chain or rings. I clean the chain and rings weekly and if I turn the crank when the bike is suspended there's no clicking.
It's only when my full weight is on the bike and pedaling that I hear a short "click-click-click" every time my right leg pushes down on the right crank/pedal. I don't know what type BB I have, it's stock '01 Trek 4500.

Any ideas? It doesn't seem to affect the bikes performance but it's kind of annoying.

Have you checked to see if the crank bolts are loose, they can create that type of noise.

also check the bb for tightness and correct torque.

um ok, how do I do that?

Here you go check this out for directions.

http://www.parktool.com/repair_help/creaking_and_squeaking.shtml

Try checking your peadls for any play, the spindle can sometimes come loose and make that annoying clicking sound.

good luck.

A long shot, but potentially very dangerous -- if a crank is starting to fail at the pedal eye or the spindle eye, it may start creaking before it actually fractures. A loose crank fixing bolt is a very likely cause of creaking from that area of the bike.

These are all good ideas. Apparent bb/crank clicking can be caused by a number of things - loose chainring bolts, loose pedals, even your saddle or seatpost. I had a squeaking sound in my crank area that was driving me crazy. I finally figured out that the way I had my cleats adjusted the rubber sole of my shoe was lightly rubbing the crank with every revolution. Chainring bolts are the easiest thing to check. Just take a 5 mm allen key and see if they are tight. Pedals take a 15 mm wrench though some have flats too narrow for a standard wrench. Checking your bb itself requires special tools. You would probably be better off letting your LBS take a look. They will only charge a few bucks to check and overhaul an old cup and cone bb with new bearings. If you need a new cartridge bb (they aren't intended to be serviced) they aren't expensive. Cup and cone bb's should be overhauled about once a year. If it has been longer than that go ahead and have it done at your LBS.

Don't get me wrong. I encourage you to learn to work on your own bike, but I personally consider the bb more of an intermediate procedure, not something to start off with.