How do I know if my bottom bracket is worn out?

[Mazz]

CONTEXT: I've been using my Allez everyday, maybe 6/7 years, through all weathers. Even on a couple of occasions gingerly riding slowly through flooded roads where the Bottom Bracket would have been submerged.

QUESTION: Are there any ways to check if your BB is still in good condition? Any tell-tale signs of wear?

Maybe, over the years, I've got used to the leg pressure on the pedals while riding, that I don't realise that maybe the BB's worn out.

 

[FrankCrank]

Check for any play, that would indicate wear in the bearings. Other than that, maybe a noisy BB would be a sign of imminent replacement due.

 

[T4tomo]

Trust me when it goes you know....
https://www.cyclechat.net/threads/my-bottom-bracket-is-making-a-hell-of-a-racket.283211/
Your allez is more likely to be a hollowtech 2 one but you get the idea

You can remove the chain and spin the cranks and listen / feel and also check for lateral play.

 

[Alex321]

As said above, if you can move the end of the crank in and out by any notocable amount, your BB is probably knackered.

If you can't, it is most likely OK.

 

[Mazz]

As said above, if you can move the end of the crank in and out by any noticeable amount, your BB is probably knackered.

If you can't, it is most likely OK.

Not sure what you mean by 'play'.
Do you mean "movement" in this direction of arrow? General "wobble" of chainset?
(not my bike, just an image off internet)

 

[Alex321]

Not sure what you mean by 'play'.
Do you mean "movement" in this direction of arrow? General "wobble" of chainset?
(not my bike, just an image off internet)
View attachment 730854

Yes.

It is supposed to move round (of course), but there i9s not supposed to be any "wobble" in the in/out direction..

 

[Ajax Bay]

Just replace it. Cheap and easy and the BB's done you 6+ years.

 

[Ming the Merciless]

Grab your pedals either side and push / pull . You’ll soon know if there’s lateral play.

 

[Mazz]

Grab your pedals either side and push / pull . You’ll soon know if there’s lateral play.

Just tried it. No lateral play. Be reyt for another 6/7 years 👍

 

[Jenkins]

Just replace it. Cheap and easy and the BB's done you 6+ years.

This - £15 for a Hollowtech BB and simple to fit (assuming you have the tools already).

 

[richardfm]

Just tried it. No lateral play. Be reyt for another 6/7 years 👍

The are other faults that don't have to involve play, e.g. clicking when peddling under load or feeling rough when spun by hand with the chain removed.

 

[Mazz]

The are other faults that don't have to involve play, e.g. clicking when peddling under load or feeling rough when spun by hand with the chain removed.

I'll check for clicking tomorrow when I'm riding out of the saddle on the uphill section. I'll take chain off too and spin the crank. Cheers

 

[Mazz]

Your allez is more likely to be a hollowtech 2

Is the name normally printed on the BB?

 

[richardfm]

Is the name normally printed on the BB?

See this video to work out what type you have
View: https://youtu.be/e-8G1G9QNX8?si=hxqsyFLCLrT4bphW

 

[T4tomo]

Is the name normally printed on the BB?

lots of different sizes and compatibility. Pictured below is a threaded Hollowtech II BB. red is part number , yellow is sizes (thread pitch, axle diameter, and ROAD for BB shell width). You also need a (very cheap) tool to remove and insert.

Some are press-fit, (as opposed to threaded) fitting and removal tools more expensive and probably not a job to attempt if you don't know what you are doing as easy to damage your BB shell.