Re: Stuck BB

On 9/20/2024 3:52 PM, AMuzi wrote:

On 9/20/2024 1:50 PM, cyclintom wrote:

On Wed Sep 18 15:30:06 2024 AMuzi  wrote:

On 9/18/2024 3:11 PM, cyclintom wrote:

On Tue Sep 17 22:11:23 2024 Frank Krygowski  wrote:

On 9/17/2024 3:59 PM, Zen Cycle wrote:

On 9/17/2024 9:10 AM, AMuzi wrote:

On 9/17/2024 7:36 AM, Zen Cycle wrote:

On 9/16/2024 4:16 PM, AMuzi wrote:

On 9/16/2024 2:00 PM, Zen Cycle wrote:

On 9/16/2024 1:57 PM, Mark J cleary wrote:

My Wilier has a stuck right cup BB. At the moment the cranks spin
fine. It has an FSA Mega Exp crankset that is the one that is not
pinch bolts but uses self extracting allen key to put on drive
side crank arm. Has the wavy washer in the set up. I think that is
why the bearings went bad because it allows moisture to get in not
sealed like a regular shimano crank and external BB.
>
The BB is of course and external BB from FSA. The let side cup
bearings went bad so I used a Shimano BB60 cup because I had a
spare one. The crankset works beautiful now. However I would like
to simply try and use the whole Shimano BB60 bracket. I cannot
however get the right side cup off. I realize it is left hand
threaded but it is really stuck. I tried putting in a vice and
using the bike to turn but no luck.

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I was going to suggest that.
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I have managed to chew the notches pretty good but it will take
the wrench at this point.
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Any suggestions on how to get the cup free. I actually think it
would be easier to simply hacksaw the cup and take it out but I
don't want to mess up the treads in BB of the bike. I will take
any and all suggestions on how to get this cup off. At the moment
the cranks spin fine because the bearings are fine on the right
side cup but I just don't like the set up. I may even go to a
shimano R7000 crankset. ]

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I'm sure Andrew may have some sage advice, but if you're beginning
to see damage to the cup, I'd suggest taking it to a shop.
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If you still want to DIY, get one of these to match your threading
first.
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https://www.amazon.com/HOZAN-C-402-Bottom- Bracket-Tap/dp/ B000BSBSLQ/
>

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Some people do like owning esoteric tools but I strongly dissuade
most customers from buying dies, reamers, mills, taps. They are only
and always subtractive, that is, they can (and often do) damage
material but they cannot add material.
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In his aluminum shell,

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Something else just occurred to me - If his frame is aluminum and the
bearing cup is aluminum, it may have galled. In that case, even
notching the cup isn't going to work. In fact, doing so may damage
the cup such that it won't be possible to replace the bearing, you'll
basically have to toss the thing.
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The question is, how do you tell if it's galled or just stuck from
corrosion or some adhesive?
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a small stainless brush is plenty for cleaning up crud from the
threads.

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https://www.sears.com/forney-70488-wire-brush- stainless- steel-with-
plastic/p-00920078000P
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Even with a lot of displaced material, a slit or at the extreme two of
them will relieve the pressure and allow removal.
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I'm not an ME, but that's not how I understood galling works. I was told
the two surfaces bond on the molecular level, I suppose one might be
able to 'peel' the two components apart, but that would either leave
and/or remove enough material such that the remaining threads would be
likely damaged beyond use.
Not being an expert in this area, I might have some misunderstanding.

>
I'm a Mechanical Engineer, but I think we need a Metallurgical Engineer
at this point. But we've been talking about parts that are not in
motion. As I understand it, galling requires relative motion.
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The problem with aluminum and steel, as in this situation, is different.
It's a layer of aluminum oxide forming at the interface, which adds
thickness to the aluminum and causes the aluminum component to
essentially clamp onto the steel component. AFAIK there's no
metal-to-metal bonding. But it's a famous problem with aluminum
seatposts in steel frames. Searching online will show that problem is
pretty common and quite difficult.
>
-- - Frank Krygowski

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The carbon fiber Willier has not been around long enough for the problem to be serious if it is a corrosion problem or not being able to force it out if it is a cross threaded problem. It is very unlikely to be cross threading so his problem is probably nothing more than corrosion. And Shimano cups are easy to force out. The material is soft enough that it would leave corrosion behine that could be cleaned by a shop with BSC thread cleaner.

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Bike is a 2013 (plenty old enough for corrosion) and you
don't know that until the cup is out.
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Andrew, do you think that Mark should be sawing off a BB instead of turning it out? It is more likely that he was turning it the wrong way and not that it was frozen with corrosion

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Mr Cleary knows right from left.

 Ok I am a decent mechanic and know the direction to turn pedals and BB. However I do have to think a bit outloud when I am going at it. I ask myself. Ok, this the drive side of the bike so the BB is left threaded and pedal is right threaded. Then we go to the non drive left side and yes the bb is right threaded and the pedals are left threaded.