Any question answered...

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Brommers in reply to @ExTra
Anyone has good or bad thing to say about T47 oversize threaded bottom bracket?

As ever, there's pros and cons.

Pros:
1. Threaded BB, so no creaking.
2. 30mm BB, so you can use cranks with a 30mm spindle.
3. Narrower than 386EVO so you can use normal BB30/PF30 cranks, not just BSA30/386EVO compatible cranks.
Cons:
1. BBs are relatively expensive, relatively difficult to source. Still cheaper than buying lots and lots of PF30 BBs which you end up destroying trying to get the little fuckers to fit without creaking.
2. You need different tools to fit them, which are difficult to source, like the Enduro Torqtite BBT-025 tool. Normal (i.e. Shimano or Rotor BSA30) splined tools won't fit because the OD of the BB flange is larger than a normal external BB.
3. If you want to chase the BB threads you need a $300 dollar set of BB taps from Paragon Machine Works. I have some, even though I don't yet have a bike with a T47 BB. I do however own some T47 BB shells. Work in progress...
Ultimately it depends what cranks you want to fit. If you're going to fit 24mm spindle cranks, or 30mm spindle cranks which will fit a 386EVO/BSA30 bottom bracket then it's not really worth it unless you are absolutely obsessed with future-proofing and want to ensure that you can fit every single type of hollow spindle crank - i.e. not square taper, ISIS or anything similar. Or cotterless cranks if you're really odd.

Basically, if it's a bespoke bike, chose your cranks, and then spec the BB to suit.

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Howard in reply to @Brommers

Threaded BB, so no creaking.
30mm BB, so you can use cranks with a 30mm spindle.
Narrower than 386EVO so you can use normal BB30/PF30 cranks, not just BSA30/386EVO compatible cranks.

The same can be said for BSA *. But everyone makes BSA compatible BBs. And tooling.

*Unless you want to use a proper BB30 crank.

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Brommers in reply to @Howard

But you can't use a proper BB30 crank in T47 either, right?

Yes, you can. The spacing on a T47 BB is the same as a true BB30 BB system*. That's what I was referring to by 'normal BB30/PF30 cranks' as opposed to BSA30/386EVO cranks which will fit in external bearings fitted in a BSA BB shell, unlike 'normal' BB30 cranks. For example, the S-Works carbon cranks will fit in a T47 BB, but won't fit in a Rotor BSA30 or FSA 386EVO BB.

* At least I hope it is. Otherwise that $300+ plus duty I spent on some T47 taps and T47 BB shells was a total fucking waste of money**.

** Ye Gods but I hate Markup. Why should using asterisks be so smegging hard?

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