# Switching Octalink BB to Hollowtech?



## Bill Dobie (Jul 22, 2014)

Hi All - Looking for simple advice from those who are more familiar than me with this issue. Doing a complete component upgrade this spring on a 2003 Trek 5200. I have everything covered now except the front crank and bottom bracket. Current set up is Dura Ace 7700 standard and OctalinkV1 english 68mm BB. Can I switch the current Ocatlink V1 BB with newer Hollowtech II BB. They look so different externally it makes me wonder if it will work? Looking to switch because it seems there are more compact crank options for the Hollowtech II. Any advice is greatly appreciated! If you need more info ask away! Thanks!


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## robt57 (Jul 23, 2011)

Bill Dobie said:


> Can I switch the current Ocatlink V1 BB with newer Hollowtech II BB.



Yes, just make sure if it is Italian you get Italian, otherwise get US.

Get the tools for the cups, the soft Aluminum does not take much to muck up not doing so.


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## ericm979 (Jun 26, 2005)

The frame is BSA (threaded 68mm) so it will take anything that fits that.
You will need two BB tools, one to remove the Octalink and one to install the Hollowtech.

Note that the current generation of Hollowtech (i.e. DA 9000) uses a smaller diameter outer cup and thus a different tool than the older ones.

Another option is Sram GXP cranks (Red, Force, etc). You will need a GXP bottom bracket. Sram cranks shift fine with Shimano derailleurs. I have them on my Shimano bikes.


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## cxwrench (Nov 9, 2004)

robt57 said:


> Yes, just make sure if it is Italian you get Italian, otherwise get US.
> 
> Get the tools for the cups, the soft Aluminum does not take much to muck up not doing so.


No such thing as a 'US' bottom bracket. And it's a Trek, so it's for sure gonna be English...which is the only current threaded option to Italian.


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## Bill Dobie (Jul 22, 2014)

I had wondered how all this translated to Sram. Thanks. That is an option for me.


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## Bill Dobie (Jul 22, 2014)

Hi CXWrench - Can you shed some light on this difference between the Hollowtech and Octalink? If I were to order a new Octalink I have width options (I think) represented as 109mm, 113mm, 118mm and 121mm. How come the Hollowtech do not have similar widths? Is it a one size fits all or am I completely missing something very simple?
Thanks,


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## robt57 (Jul 23, 2011)

cxwrench said:


> No such thing as a 'US' bottom bracket. And it's a Trek, so it's for sure gonna be English...which is the only current threaded option to Italian.



You know exactly what I meant, stick the Symantecs, all due respect.

Excuse me for not typing ISO. When we get to a certain age, the brain farts become more prevalent. I am there, so as Steve Martin would say "EXCUSE... ME!!"

I always looked at it as Itey or US. [Itey; as in Breaking away, them ini things] Although in the PC world we live in, I know I will be sorry I typed that.


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## ericm979 (Jun 26, 2005)

Bill Dobie said:


> Hi CXWrench - Can you shed some light on this difference between the Hollowtech and Octalink? If I were to order a new Octalink I have width options (I think) represented as 109mm, 113mm, 118mm and 121mm. How come the Hollowtech do not have similar widths? Is it a one size fits all or am I completely missing something very simple?
> Thanks,


The width on the Octalink BBs is the axle width. With modern cranks, the axle is in the crank, not in the BB. So the BB is one size fits all.


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## Bill Dobie (Jul 22, 2014)

Ahhhh. That clears it up. Thanks for the help!


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## velodog (Sep 26, 2007)

robt57 said:


> You know exactly what I meant, stick the Symantecs, all due respect.
> 
> Excuse me for not typing ISO. When we get to a certain age, the brain farts become more prevalent. I am there, so as Steve Martin would say "EXCUSE... ME!!"
> 
> I always looked at it as Itey or US. [Itey; as in Breaking away, them ini things] Although in the PC world we live in, I know I will be sorry I typed that.


I'm not trying to be argumentative, but it's more than semantics. The man has asked a question to better understand his job at hand, and using the standard nomenclature makes the understanding that much easier. 

I have a good friend, that is a retired machinist, who calls anything metric threaded "Chinese threaded". I know exactly what he means, but someone who doesn't may find himself looking for, well you know.


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