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BB coming loose?!

canadmos

Cake Tease
May 29, 2011
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Canaderp
Cane Creek sent me a new BB under warranty, so props to them. It hasn't come loose after a bunch of rides, but I have the preload set feather light; one other thing I noticed is that even a fraction of a nudge on the preload ring would cause the bearings to bind majorly.

Going to replace the bb this weekend and see if that changes. Maybe the mysterious creek will go away too...
 

jonKranked

Detective Dookie
Nov 10, 2005
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Cane Creek sent me a new BB under warranty, so props to them. It hasn't come loose after a bunch of rides, but I have the preload set feather light; one other thing I noticed is that even a fraction of a nudge on the preload ring would cause the bearings to bind majorly.

Going to replace the bb this weekend and see if that changes. Maybe the mysterious creek will go away too...
did they give an explanation of the issue?
 

canadmos

Cake Tease
May 29, 2011
13,944
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Canaderp
The stupid thing was loose at the start of last night's ride. Ugh. I definitely gave it three extra ugga duggas last time.

Oh well...putting the new one on tonight and will try a plastic spacer as mentioned by @Westy I think.
 

canadmos

Cake Tease
May 29, 2011
13,944
11,136
Canaderp
So I replaced the drive side BB last night and.... the new one feels exactly the same.

I fiddled around with them and even the non-drive side is crunchy, if I apply any preload to the inner race of the bearing. The following paint photochop illustrates this with the red/green arrows. While holding the BB cup in my hand, I pressed and spun the bearing with my fingers; while applying load towards to the threaded side, the rotation does not feel smooth. While spinning the bearing and "pulling" away lightly, towards to the crank side, the bearing is super smooth. All four of the BB cups that I now have do this. On the BB cup that I replaced, if I applied enough load with my fingers, the entire bearing/cup would lock and spin - I have a hunch this is why it keeps coming loose, no matter how tight the bb cup is.





Is it possible that the inner race is touching the BB cup itself, when load is applied? Reason I might suggest this, is that when looking at the backside of the bearing, there doesn't appear to be any space between the inner race and the BB cup (I don't have feeler gauges to actually test) and I can't see the edge of outer diameter of the inner race.

Futher to this point, Hambini conveniently took one of these Hellbender 70 BBs apart in a recent video. He finds there is no lip or spacer in the BB cup, so if I interpret what he says, if the bearing is pressed in all the way, it will bind on the cup? If this is true, are these just being assembled wrong with the bearing pressed in all the way or without any sort of spacer? Seems like a dumb simple thing for Cane Creek to miss, considering majority of their business is built around bearings?

13:06 for the Cane Creek bearing removal

What do our e-engineers and real engineers think? @Westy ?
 
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Westy

the teste
Nov 22, 2002
44,810
10,457
Sleazattle
Certainly weird. No new bearing should feel crunchy and that feeling could be the inner race rubbing on the cup. But that would be a really really dumb design, without seeing a cut-away view of the cuts hard to say, but no good design should allow for that. What you are describing also sounds like a set of bearings that were pressed in backwards. I assume that BB bearings are some shallow angular contact bearing that can take some side load in one direction but will not in the other. Is it possible for you to get the bearing part number to see if it was installed correctly?

Example:

 
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canadmos

Cake Tease
May 29, 2011
13,944
11,136
Canaderp
Tried to take pictures to show how tight the inner race is up against the bb cup. I can't fit a sliver of paper between the inner race and the cup.





Notice how you can't see the outer edge of the inner race? It must be rubbing on the bb cup with even the lightest preload...
 

canadmos

Cake Tease
May 29, 2011
13,944
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Canaderp
If the cranks were even at all questionable, I'd totally switch over to Shimano cranks and BB without even thinking. I hate the single tight as shit bolt on Race Face cranks and fiddling with the dumb 2mm screw on the preload ring...
 

canadmos

Cake Tease
May 29, 2011
13,944
11,136
Canaderp
I took my bike apart for ye ole annual spring lube and grease job.

And found that the damn drive BB is loose again. :( Time to bring up the issue with Cane Creek again.

I also noticed that on the drive side, with the BB spacer and ISCG bracket, that the BB on that side has about half the thread engagement as compared to the non-drive side. Thoughts - could that coupled with the binding bearing be why the drive side BB always spins loose, no matter how many ugga duggas I give it?
 

Adventurous

Starshine Bro
Mar 19, 2014
7,126
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Crawlorado
Don't use press fit bottom brackets they said. Threaded is superior they said.
I have 5 years and 1,000+ miles on the OEM press fit BB on my SB5. Never made a peep, and is still silky smooth even though I've never done a single thing for it.

Not saying they can't be a problem, but anecdotally speaking, it's been great for me.
 

jonKranked

Detective Dookie
Nov 10, 2005
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I have 5 years and 1,000+ miles on the OEM press fit BB on my SB5. Never made a peep, and is still silky smooth even though I've never done a single thing for it.

Not saying they can't be a problem, but anecdotally speaking, it's been great for me.
n=1 is not a statistically significant sample size.
 

Westy

the teste
Nov 22, 2002
44,810
10,457
Sleazattle
I've had two problem free press in bikes. I do have to replace my threaded Durable (LOL) Unified BB about every ten months.
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
18,038
2,201
01776
my 3T and BMC have been creak and problem free since install. I even ride the 3T too. Shimano BB in one and FSA in the other, neither over $35. Both plastic shell doo-dads, but both designed properly.

Had a raceface which I chased creaks on, but that was 30mm spindle in a BB92, which is not gud.

I'd still take a BSA over a press-fit, but I think pressfit is OK if designed correctly.
 

iRider

Turbo Monkey
Apr 5, 2008
3,477
1,400
Only pressfit I own is a Spanish BB on the pumptrack bike.
BTW: how can a BSA BB come loose? I know that Italian BBs do this because of the not reversed threading, but never have seen this in BSA.
 

canadmos

Cake Tease
May 29, 2011
13,944
11,136
Canaderp
Only pressfit I own is a Spanish BB on the pumptrack bike.
BTW: how can a BSA BB come loose? I know that Italian BBs do this because of the not reversed threading, but never have seen this in BSA.
When the bearing binds, the whole thing spins clockwise, which is the way it loosens.

When the bearing is spinning freely, the rotation on the outer race is the opposite way that the cranks are spinning...if I'm visualizing it correctly, no? So when not binding, the thing should never be able to loosen itself - and no, I'm not coasting down every trail back pedaling. :D
 

jonKranked

Detective Dookie
Nov 10, 2005
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some questions.....

how old is your frame?

how many different bb's have you gone through on it?

how often do you pull your BB for cleaning/service?

are you using the spacer sleeve with the BB?

have you tried another set of cranks with the bb?
 

iRider

Turbo Monkey
Apr 5, 2008
3,477
1,400
When the bearing binds, the whole thing spins clockwise, which is the way it loosens.

When the bearing is spinning freely, the rotation on the outer race is the opposite way that the cranks are spinning...if I'm visualizing it correctly, no? So when not binding, the thing should never be able to loosen itself - and no, I'm not coasting down every trail back pedaling. :D
True, did not consider bearings binding.