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Discussion Starter · #1 ·
Hi all,

I'm hoping some of the more experienced mechanics on the board (Hollister, SSMike?) could lend a hand with this one.

We have a 9spd FSA carbon crank on a Shimano Ultegra Octalink BB. Non-drive side is stuck. Popular theory is there's corrosion between the aluminum insert and the steel BB axle. Whatever it is, it's good and stuck.

The owner says the outer threads on the crank are stripped. These are the threads to which one would normally use to fasten a self-extracting washer with bolt. But cranking on this sucker pulled the washer right out of the crank, thus ruining any chance of getting a crank puller in there.

My first suggestion was a tuning fork wedged between the crank and BB, but theres no room for one to fit. I can think of several other violent ways to get this off there, but the owner wants it done civilized.

Any suggestions?





Thanks
 

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velocipede technician
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can you wrap some foil or thin shim stock around the tool to try and beef up the threads?

octalink, damn. maybe carefully ride it around the block to loosen it like a stripped square taper?

all else fails get out the pickle fork

hope someone else has a better answer
 

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Discussion Starter · #3 ·
hollister said:
get out the pickle fork
I think you and I are thinking of the same thing...



But none had one thin enough to wedge in there. Plus, I'm thinking that would mung up the aluminum BB cup, which would make getting a tool on that impossible...
 

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velocipede technician
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ameybrook said:
I think you and I are thinking of the same thing...



But none had one thin enough to wedge in there. Plus, I'm thinking that would mung up the aluminum BB cup, which would make getting a tool on that impossible...
the crank must come off, that BB must be removed?

we will not be beaten

you have a dremel?
 

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Assuming that the crank is now useless, can't use remove the BB using an older style BB tool that grips the outer prongs of the BB. You can remove the BB still attched to the crank arm (assuming only hte non-driveside is stuck). It will render the crankset and BB useless, but the frame will be okay.
 

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hollister said:
octalink, damn. maybe carefully ride it around the block to loosen it like a stripped square taper?

all else fails get out the pickle fork
I like hollister's first thought there. Might not take much to work it loose.

Why does it have to come off? BB need replacing? If the bb needs replacing and you are going to install the same crank, he'll have the same problem the next time the crank arm needs to come off. At this point, the crank arm is shot if there is no way to ever remove it again.

All common methods to coax the arm off will likely damage the arm anyway. Heat will damage the bonding of carbon to aluminum. A pry bar will damage the carbon. Something like a large bearing puller might work if you can protect the back side of the carbon arm.

I can't remember if some of the Campy or TA cranks take a slightly larger diameter crank puller. Can you force one of these into the arm and use that larger diameter Octalink pipe adapter?
 

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ameybrook said:
One of the Jeep nuts in the office says this might work:

https://www.matcotools.com/ProductImages/mst3561-62-63.jpg
That should work. The bb wrench flats already look a little thrashed. How much is he paying per hour of labor? It must be an expensive BB. The crank is trashed and an hour of labor probably pays for a new BB so I would have just cut it off.
 

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ssmike said:
I like hollister's first thought there. Might not take much to work it loose.

Why does it have to come off? BB need replacing? If the bb needs replacing and you are going to install the same crank, he'll have the same problem the next time the crank arm needs to come off. At this point, the crank arm is shot if there is no way to ever remove it again.

All common methods to coax the arm off will likely damage the arm anyway. Heat will damage the bonding of carbon to aluminum. A pry bar will damage the carbon. Something like a large bearing puller might work if you can protect the back side of the carbon arm.

I can't remember if some of the Campy or TA cranks take a slightly larger diameter crank puller. Can you force one of these into the arm and use that larger diameter Octalink pipe adapter?
Yeah, ride it around to break the bond.

The other side of the park crank removal tool has the TA threads. I think it would be too big.
 

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Discussion Starter · #13 ·
He already went to the LBS. They tried EL's suggestion, but quit out of danger of damaging the BB threads. Basically they just didn't want to be responsible for ruining the frame. They had no other suggestions for the crank removal.

Handed the frame back and said you're SOL. :rolleyes:

I'm suggesting the two claw puller with a couple dimes stuck in there for leverage. We will see...
 

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Fillet-brazed said:
The other side of the park crank removal tool has the TA threads. I think it would be too big.
having just pulled some TA's, yes

much bigger(ok, just a little)

hmm, how to tap to the bigger threads while still on the bb?:idea:
 

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ameybrook said:
He already went to the LBS. They tried EL's suggestion, but quit out of danger of damaging the BB threads. Basically they just didn't want to be responsible for ruining the frame. They had no other suggestions for the crank removal.

Handed the frame back and said you're SOL. :rolleyes:

I'm suggesting the two claw puller with a couple dimes stuck in there for leverage. We will see...
Ive used dimes before with no luck. Very soft. I ended up easily pushing them right into the axle so be careful. It was kind of a pain to get them out.
 

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Fillet-brazed said:
Ive used dimes before with no luck. Very soft. I ended up easily pushing them right into the axle so be careful. It was kind of a pain to get them out.
A stack of 3 or 4 dimes would be better, no? The top couple will still be deformed, but at least you're spreading the load. Or Park crank pullers come with that thick steel flat surface that can be unscrewed. See if that will fit in there for the 2 jaw puller to push against
 

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If the drive side crank came off, put a cone wrench, or similar "shield" between the arm, and the BB cup. Then, after soaking the offending items in penetrating oil for a bit, remove the BB from the drive side, the shield protects the non drive cup, so it can come off after the fact. Simple, free, and with the number of threads engaged, I highly doubt you'll strip the bb shell. :thumbsup:
 
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