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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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gbj_tester in reply to @Brommers

Narrower than 386EVO so you can use normal BB30/PF30 cranks

BB30 is a bit pointless on modern dérailleur geared bikes since the Q-factor minimum dictated by chain clearance in top gear can be achieved with 386EVO. You might as well enjoy the benefits of an 86mm wide shell, although there's no reason why the touted benefit of threaded rather than pressed (i.e. it permits frame manufacturers to avoid having to do press fits properly) wouldn't be just the same in a wider shell.

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Brommers in reply to @gbj_tester

BB30 is a bit pointless on modern dérailleur geared bikes since the Q-factor minimum dictated by chain clearance in top gear can be achieved with 386EVO. You might as well enjoy the benefits of an 86mm wide shell, although there's no reason why the touted benefit of threaded rather than pressed (i.e. it permits frame manufacturers to avoid having to do press fits properly) wouldn't be just the same in a wider shell.

True. The reason I invested in T47 taps and T47 BB shells was because I really really like SWorks FACT carbon cranks for no particularly good reason other than that I managed to pick up a pair for 47 quid. I'm certainly not averse to 386EVO cranks, having a very extensive collection of Rotor 3D+ cranks as well.

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