Any question answered...

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.

If you are using a BSA bb with internal di2 the bb cups may have threads that are too long - Chris King and Hope bb would not work in my Isen as their threads would block the hole from the bb to the chainstay. - I had to resort to shimano as the threads are shorter.

Would it be possible to turn down the length of the cap with the threads on it? I know what you mean about the Hope BBs (I don't have any Chris King BBs... yet) but I can't see any real reason why the threaded sections are so long on them.

@Dammit, what bikes are they? Just out of interest.

My Talbots: Gnarmac and Gravity Shadow

My Talbot's

How much for a pound of bananas?

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.

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?

Ah yea. Like this thing

$169...

Yep, that's a T47 30mm internal BB. To be fair, there are cheaper alternatives to C-Bear in pretty much every department. Wheels Manufacturing or White Industries T47 BBs are 99 dorrah, for example. Not cheap, but not that much in the great grand scheme of things. Let's face it, if you're even thinking about a T47 BB then it means you're buying an artisinal bespoke frame, which is not going to be a budget option.

Not cheap, but not that much in the great grand scheme of things.

Dunno. Depends on how many you chew through I guess. PF30 in my experience has been pretty bomb proof - three bikes with it, all off road types, two of them all weather, £16 investment in one replacement BB in cumulative 3500 miles. Hammering the fucker out wasn't very nice though I have to admit.

But yeah if you are using that type of BB you are using spendy cranks too so what's another couple of beer vouchers.

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.

Ye Gods but I hate Markup

Probably not as much as you hate Markdown

i think this may be possible but don't have the knowledge to be certain

Yep, that too. Poxy thing.

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.

I am having internal everything, so this might well be the reason why the T47 BB idea. It's also a titanium frame, so this might also have something to do with it due to the tube size?

As for crankset, as we discussed a few pages back, I have my eyes on the Shimano XT M8000 1 x 11 because I am having flatbars.

This is one of the brands recommended to me and works with the the M8000...

https://rideworks.cc/shop/t47-bb/

Anyone heard of them? They are relatively new and is UK based.

Also, it seems like some brands do offer both 24mm and 30mm and prices are the same - very expensive... :-(

I am having internal everything, so this might well be the reason why the T47 BB idea. It's also a titanium frame, so this might also have something to do with it due to the tube size?

I'd ask why a BSA shell is unsuitable and what compromises they'd need to make to make a BSA shell suitable.

I have a pretty hefty downtube on a Ti bike welded to a BSA shell, looks fine. But everything is external. Oh when life was simple.

Cheapest 73mm hollowtech cranks? Deore or is there anything else?

Got SLX cranks you can have cheap?

What state are they in? And how much?

Sorry to spam this but it's doing my head in.

Is there a reason my gear lever boss has been brazed on at right angles to normal?

is there any reason I couldn't install etap hyrd on the canyon ultimate cf mechanical frameset?!

I bet its for a specific shifter, i know thats not useful, but if you can ask the original seller how they had it built it may help.

Good guess. @BigH do you have the details of the guy you got it from?

Have you asked Retrobike? Or TT forum, if you dare...

Got a pic of a shifter attached? Maybe the Bodge thread is a better place to ask...

If it comes to it, you could always fit band-on shifters, right?..