[Closed] How to fit a square taper bottom bracket into a PF30 shell?

Not sure PF30 and BB30 are the same;

This implies a different diameter hole;

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No problem, youi'll have room to spare.

I did look into this a while back, I don't think it can be done (from memory) without permanently fixing a custom made threaded sleeve into the PF30 shell.

I don't think those types of adaptor are suitable for square taper (Square taper doesn't then support itself against the frame; so you are putting huge strain on a small amount of loctite.. rather than using the threaded sleeve to allow an outboard bearing to then squeeze up against the frame to take the strain off the loctite/sleeve, if that makes sense.)

So doable but not easy or straightforward was my end result (I think)

Op if you haven't already seen it the same question has been asked on the product page of the adapter you linked to. FWIW the answer is yes

thanks. What about the Praxis converter ... anyone used this?

https://www.sigmasport.co.uk/item/Praxis-Works/BB30-to-24mm-Converter/1VMZ

thanks rocketman - looks like that fix is a semi-permanent one tho 😯

Can't you get outboard bearing Bottom Brackets that fit in pf30 holes?

Edit: damn, need for sq taper, apologies OP.

FWIW BB30 shell ID is 42mm whereas PF30 is 46mm - never seen a PF30 to BSA threaded press-fit adaptor but there might be one out there!

The Praxis adaptor is for use with a 24mm crank like Hollowtech 2.

[url= http://www.chainreactioncycles.com/fsa-pf30-threaded-adapter-b3167-/rp-prod129936?gs=1&utm_source=google&utm_term=&utm_campaign=Chain+Reaction-UK-PLA-PLA-All-DT-SE-Shopping+QLB+Generic+Desktop&utm_medium=base&utm_content=mkwid|sI2516pSV_dc|pcrid|161849859102|pkw||pmt||prd|466165UK ]crc linky[/url]
that one?

thanks all ... how's about this one, looks less permanent

http://www.chainreactioncycles.com/sram-pressfit-30-to-bsa-adaptor-kit/rp-prod71306?gs=1&utm_source=google&utm_term=&utm_campaign=Chain+Reaction-UK-PLA-PLA-All-DT-SE-Shopping+QLB+Generic+Desktop&utm_medium=base&utm_content=mkwid%7CsfWL42C6p_dc%7Cpcrid%7C161855055965%7Cpkw%7C%7Cpmt%7C%7Cprd%7C271762UK

If you read the Q&A's on that CRC page, you will see that it is not suitable for cartridge bottom brackets (which pretty much rules out square taper) and that according to CRC "external cup bottom brackets are intended for use with this adaptor".

It seems to me that you are trying to marry two standards which were never intended to be compatible. I suggest you provide more detail about what you are trying to achieve (why square taper etc.), and people may be able to provide better advice and/or point you in the direction of alternative options.

slowster - I guess I am. It was simply as I found the old Shimano square taper b/b longevity brilliant, and I've a nice Middleburn RS7 chainset that I'd like to use. My current set up Shimano XT with Gussett PF30/24 b/b does a great job when the bearings are fresh, just they do wear quickish.

I agree with you about how good Shimano square taper bottom brackets are, but I think you might do better to store your Middleburn chainset and plan that your next frame will be standard BSA thread, and in the meantime start a new thread asking what are the best bearings to use with your current set up (obviously check for previous threads on the subject first).

I fear you're right!

Why couldn't you use the FSA adaptor in the CRC link? (Genuine question - I don't know if it would work.)

http://www.chainreactioncycles.com/fsa-pf30-threaded-adapter-b3167-/rp-prod129936

What about .....

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conversly I wept with joy when sq taper was shipped off to biking Valhalla, as I endlessly bust spindles...

good advice from slowster, HT11 is pretty good in terms of longevity these days (if fitted properly)

Why couldn't you use the FSA adaptor in the CRC link? (Genuine question - I don't know if it would work.)

The internal diameter of the Praxis one narrows in the middle, which is why a cartridge square taper bottom bracket will not fit it according to the CRC Q&A page.

The FSA one will accept a square taper cartridge according to the CRC Q&A page, but the OP was concerned about it being semi-permanent. Personally, I would not want to use a cartridge bottom bracket in such an adapter, since I cannot help thinking that the repeated torque applied in installing and removing the cartridge to replace it when it has reached the end of its life or develops a fault, is going to lead to problems with the press fit at some point.

I agree, the only way I would consider a sleeve for square taper would be if someone (competent) was willing to bond it in place permanently (which would also void any warranty if that matters.)