BIKE: Creaking bottom bracket

[Robert M Farr]

The bottom bracket bearing cups (the threaded parts) moving around in 
the bottom bracket housing (the frame) can be a source of creaking. The 
creaking may also be coming from your seat post, either at the seat or 
the seat clamp at the seat tube of the frame.

Because it's not something the typical prospective buyer looks for, 
bottom brackets are typically some of the most marginal quality parts on 
a bike. And the threads on bottom brackets aren't always machined to the 
tightest tolerances either. That means they're often sort of a loose fit 
that refuses to stay tightened after assembly.

If you don't already have them, get the appropriate tools necessary for 
disassembling your crankset and bottom bracket. (NOTE: sometimes, not 
everything is righty-tighty/lefty-loosey -- be prepared to encounter 
left-hand threads) Then remove your cranks and get at the bottom bracket 
bearing cups on both sides. You'll probably find that at least one side 
is already loose. That's probably where your creaking is coming from. 
Clean out any spooge in the threads and reassemble using threadlock 
compound like Locktite TM which comes in blue, red and green "flavors."

I'd only use the blue low-strength variety on a bike application 
although I've seen the green very-high-strength variety recommended for 
problem bottom brackets. Be warned: the green variety requires lots of 
heat and muscle to bust loose. In other words: It's best thought of as 
an alternative to epoxy or superglue.

If the creaking is coming from elsewhere -- like your seat post -- 
grease or anti-seize compound may help.

Robert Farr
Austin, TX
bobfarr

Kevin Winert wrote:
> I have a very loud, creaking bottom bracket (although
> the creaking could be my knee). I read on line that
> usually this means it needs to be tightened or
> adjusted, perhaps greased.
> 
> Does anyone have experience with this?
> 
> Thanks,
> Kevin Winert
> kwinert1
> 
> 
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