Tim wrote:
> On a 2003 TREK w/ approx 700 miles?
> I hear a creaking/ almost popping sound under heavy acceleration/ load,
> however I a not positive if it is the bb but I think so.
> Anyway I removed the crankarms and bottom bracket to investigate and it
> appears perfect (smooth bearings, appearance and all). Any ideas? ...or
> should I even be concerned at all? Any insight would be appreciated.
To be sure it's the BB, you might want to eliminate other possibilities
first:
1. Slight seat post movement in frame (do you still get the creaking
sound when applying load while *out* of the saddle?). I had this noise
once and swore that I'd cracked my frame. I used a very thin piece of
rag (1 cm x 15 cm) that I shoved down together with the post, to dampen
the movement. Noise disappeared.
2. Cassette lockring slightly loose (tighten same, or try someone else's
back wheel for comparison)
3. Chainring bolts loose (tighten)
4. BB cups loose (you've been there already)
5. BB bearing. Check again; twirling and pushing it around for more than
30 seconds - out of the frame - might reveal a place where you get play.
I had this problem with a Campag AC-S, but the noise was an occasional
low-pitched "bang". I may have broken a bearing; since I had ridden less
than 2000 km I returned it to the LBS + got a new one.
6. Pedal bearing (especially if you get the noise only on one side). If
the pedal is bad, or loose, you should be able to feel this through your
foot, though.
I'll put my money on 1) above.
Tell us what it was, in any case.
/Robert
