i'm hoping i'm not thinking clearly and this is an easy problem to fix. i started hearing this weird noise when i would need to backpedal hard to come to a stop..you know, the stops that don't need a skid but you need to slow down. well i decided it meant i should probably take my bottom bracket apart and give it some tlc. i greased everything up and put her back together..problem solved? i thought so! the next day i try to stop the same way and it makes the noise again so later that day i take off my crank and my non driveside bottom bracket thingy is loose. i tightened it and then today it seems like the problem is still there.. any ideas?!

Can you describe said noise?

Yes, is it a squeak? A rattle? Does it tell you to kill?

it almost sounds like a pop..i'm ready for it to be something really horrible..like the bottom bracket threads being shot or something like that.

Did you grease the threads? Is the BB new?

lets just say there might be more grease in the bottom bracket area than bottom bracket..ok, not really but yeah i greased the crap out of it. it is a new bottom bracket..new bike actually. a few days prior to all of this was the first time i had even touched the bottom bracket just because i was doing a all around bike tightening.

A bike repair stand and a stethoscope should allow you to pinpoint the source of the noise. If you don't have a stethoscope, use a piece of rubber tubing.

RFM

Try using teflon/plumbers tape on the bb threads , it will stop things working loose and make your BB a little snugger.

The pop/click sounds like a BB adjustment issue, which you seem to have discovered is caused by your BB being loose. If you're still getting it when everything is snug then its a bearing issue which means replacing the bearings or BB.

I would also check your adaptor sleave/cup is not cracked. Some of the cheaper Sealed BBs have plastic ones and it can be damaged if not installed correctly.

Good luck

Since it is a brand new bike are the wheels new? If the spokes are not properly tensioned you will hear a ping/pop as they settle in, kind of like guitar strings when you put new ones on the ol' axe.

My favorite "pop" theory though is the ungreased pedal thread. This will make the most awful/scary sound sometimes if the threads are not greased. Also check your chainring bolts to make sure they are on tight.

A pop sounds like a loose crank arm or cog perhaps. Do you feel any sudden shift when it makes the noise?

it's definitely a pop in the bottom bracket area. i only hear it when i slow down hard and when i would trackstad (when being the correct word since i have stopped since this noise started). it's sounds/feels like it's on the left side so i think i'm going to try fixedpp's idea to see if that makes it more snug and stops the noise.

it feels like there might be a little bit of a shift but i don't know if it's the bottom bracket or me trying to pedal in the other direction to avoid the noise happening again. one of those things where you don't know if it's really there or if your mind is just scaring you..

I get the same feeling sometimes too. I feel this *pop* sensation in my feet sometimes when I'm starting from a standstill, or after really mashing up a hill. It almost feels like the chain is trying to jump off the ring.
I've been trying to track it down for the past week. So far:
0. cleaned and lubed chain
1. Replaced BB (old one was dead)
2. tightened chainring bolts
3. tightened cranks
4. checked pedal tightness.
5. checked chainline (about 1mm off)

This has reduced the popping by about 75%, but it's still there. I guess i'll tear it down again this weeked. and check the BB tightness.
Maybe I need a new chain?

what about the ole seatpost and saddle, are you sure its a BB noise. I have had the mysterious noise too and people have suggested checking out the seatpost and sure enough. Returning the favor.

Are the pedals new? If not, it could be that the bearings are shot...

me?
My saddle rails to creak every so often, but I'mpretty sure it isn't the source of this problem, but I'll check. I can actually *feel* the popping in my feet, so I doubt that it's the seatpost.

pedals are 4 month old eggbeaters.


whoa! I just removed the dustcaps on the ends and found out that I have about 5mm of play in the pedal bodies! is this normal?

take a look at your cog, too. A bent tooth will pop and ping as the chain jumps around under heavy load.