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You won't find them for $100USD unless they're dull/broken.

I purchased from 365cycles on ebay.
A quick search (literally 5 seconds) shows a set of cyclus taps available in Italy for a good price.

IceToolz might make a set of T47 taps that are low cost . . . and somewhat low quality. They'll be fine for aluminum frames or maybe a dozen steel frames but not much more than that. Use copious amounts of cutting fluid and don't force things.

You will need to set up an account with QBP and I'm not sure that they'll do that since you seem to be outside of the US.
 

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Discussion Starter · #9 ·
I still don't understand why anyone would choose T47. It makes no sense.

Regardless, in the US, I just purchased a set of taps for a repair (paid for by them) and they cost about $400 wholesale. Now I have them but can't see why I'd ever use them.
Hi Peter
I know it make no technical or engineering sense, but for a road or gravel bike where someone is seeking internal cable routing it's a convenient option. I know there are many views on internal routing, but if that the ask, then it helps with routing the rear brake hose.
 

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Discussion Starter · #11 ·
Why build a worse bike around the routing? That makes even less sense.
I agree that it's a worse bike, weaker in certain areas and definitely a pain to change cables/hoses. But some people like the aesthetic appeal of internal cable/hose routing. For those that do, the T47 is a convenient option, but I agreed not the best technical option.
 

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* can opener and worms at the ready *
Can you explain why it makes no sense?
1. It's very large and heavy when there are more compact and lighter shells freely available.
2. It's threaded, which is an incorrect interface on the frame.
3. It's expensive to produce
4. It forces bad geometry in mountain bikes
5. It solves no problems.
 

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Discussion Starter · #14 ·
1. It's very large and heavy when there are more compact and lighter shells freely available.
2. It's threaded, which is an incorrect interface on the frame.
3. It's expensive to produce
4. It forces bad geometry in mountain bikes
5. It solves no problems.
Hi Peter
Some interesting stuff there. Agree with 1 and 3 which come down to design and wallet considerations. I'm really interested to understand more on 2 & 4 if possible, just for my learning in terms of the bad geography and incorrect interface?
5 I guess is whether you think it helps internal routing if that is what a customer wants and whether it helps to solve that. Not fundamentally a problem to solve as such.
 

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I'm really interested to understand more on 2 & 4 if possible, just for my learning in terms of the bad geography and incorrect interface?
5 I guess is whether you think it helps internal routing if that is what a customer wants and whether it helps to solve that. Not fundamentally a problem to solve as such.
RE:
2 - Bearings are not located using threads. That is not how engineering works. Bearings are located with bores. Show me a bearing on a car, motorcycle, airplane, machine tool, submarine, etc that is located with threads, you can't (baring some insane special case). Definitely not for a simple spindle.

4. Most quality hardtail mountain bikes will have 400-410mm rear centers, a little longer for very tall people. There is very little room between the tire and crank shell when using 622-62 tires and a 1.75" shell. Going to a 2" shell only makes this worse. I just don't see it pulled off well.

5. Internal routing is not a solved problem. Internal routing is a problem. Internal routing is a very low performance choice. It's sick on Instagram, not so much for folks that take the bike seriously. I'm sure folks want it but then again, I'm not interested in low end bikes.
 

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Discussion Starter · #16 ·
RE:
2 - Bearings are not located using threads. That is not how engineering works. Bearings are located with bores. Show me a bearing on a car, motorcycle, airplane, machine tool, submarine, etc that is located with threads, you can't (baring some insane special case). Definitely not for a simple spindle.

4. Most quality hardtail mountain bikes will have 400-410mm rear centers, a little longer for very tall people. There is very little room between the tire and crank shell when using 622-62 tires and a 1.75" shell. Going to a 2" shell only makes this worse. I just don't see it pulled off well.

5. Internal routing is not a solved problem. Internal routing is a problem. Internal routing is a very low performance choice. It's sick on Instagram, not so much for folks that take the bike seriously. I'm sure folks want it but then again, I'm not interested in low end bikes.
Good info, thanks Peter.
 

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* puts can of worms back on the shelf *

Thanks Peter. I too agree with 1 and 3 and perhaps disagree with 2, 4 and 5. On point 4, I'm more a road/gravel rider so massive tyres and short-as-possible chainstays are less of a concern for me, I'll let those with greater knowledge and experience weigh in on that one.

On point 2, I'm sure there is more than plenty of anecdotal evidence for and against threaded and press-fit BBs on bikes, and even more vociferous arguments (cough hambini). As with pretty much every engineering problem, if you make it properly it will work as intended and we all know that mass-produced bikes are rarely made to the correct tolerances, especially with press-fit BBs. And I hope that most of the DIYers and boutique builders on this board will take more time and effort to do it right, facing, honing, chasing, whatever. But I disagree that the bearings are located using threads - whether it's a BSA, Italian, French, Swiss or T47 threaded BB, the bearing is located in a bore, within a threaded cup (pedantic maybe?). As long as those cups are machined to tolerance and the BB shell is too, there is no reason to believe that the bores - and bearings - won't be properly aligned.

On point 5, it might solve the problems caused by badly-made oversize press-fit shells. But that of course is much easier to remedy by just making press-fit shells properly.

For the record, I see no reason to use anything other than BSA or PF30, as long as they are made to tolerance. And I'm not an engineer so don't listen to any of my advice :ROFLMAO:
 

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On point 2, I'm sure there is more than plenty of anecdotal evidence for and against threaded and press-fit BBs on bikes...
The engineers aren't debating this. There is just one answer. It's the kids in bike shops that imagine that they know anything about engineering or mechanics that seem to think that threads make any sense. Really. Show me another example anywhere where spindle bearings are threaded into place.

I've been using PF41/86-89.5 for the past decade. It's really the only interface that should be used on bikes currently. So, of course the whole industry is moving away from it because the 13 year olds don't understand it. EC49 was an amazing interface that everyone gave up on also. This always comes down to marketing to children rather than making well engineered product.
 

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