New Trek w/ T47 BB

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AnkitS
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by AnkitS

@madik Yes but 24mm axle cranksets are generally heavier than BB30 and dub cranksets right? What would the net loss/gain be after accounting for aluminum sleeve, bottom bracket, and cranksets when compared to bb90 is the real question we should be asking.
Last edited by AnkitS on Thu Jun 06, 2019 7:09 am, edited 1 time in total.

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TobinHatesYou
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by TobinHatesYou

silvalis wrote:
Thu Jun 06, 2019 7:02 am

I think you've missed the point. It's a non-standard standard that can't be used in any other T47 bike. All they've done is fufilled paragon's comments on 7 (now 8 ) different T47 widths. Also it's really irritating that T47 doesn't have any nomenclature to do with it's bb width other than the "standard" and "wide" (which isn't 85.5).

I mean you said it yourself, T47 already comes with different sized cups to work with 86.5mm shells and 68mm shells. Trek adding 85.5mm to the mix is a minor annoyance at worst. It's an unlikely scenario that you would take a Trek T47 BB and transfer it over to another frame. Even then we're talking about 1mm and there's a chance you could back the preload adjuster all the way out and it might be fine. Or do what others have done in the case BB30A/PF30A and maybe remove the adjuster altogether, then add washes/spacers as necessary.

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silvalis
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by silvalis

That's what trek is saying - the preload adjuster on sram and shimano cranks will fix it. So really all it takes is a shell slightly too narrow, then it's out of spec and you're throwing spacers in.
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TobinHatesYou
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by TobinHatesYou

silvalis wrote:
Thu Jun 06, 2019 7:13 am
That's what trek is saying - the preload adjuster on sram and shimano cranks will fix it. So really all it takes is a shell slightly too narrow, then it's out of spec and you're throwing spacers in.

No I mean, the only detriment to Trek creating a narrower shell and their own cups each being .5mm wider is cross compatibility if you choose to move the cups over to a different bike with an 86.5mm shell. If a Trek frame needs 1mm total in spacers between the shell and cups, so be it...it's not a huge deal.

e: Trek cups in an 86.5mm shell would result in flange to flange distance of 87.5mm. I bet the preload adjuster could back out enough to fit that anyway. If not, you could probably do what others have done in the past and remove the adjuster altogether and fill in the gap with spacers.

ee: The Trek/Praxis 85.5mm width is probably for the best and I could see it becoming the defacto "wide" standard in short order.
Last edited by TobinHatesYou on Thu Jun 06, 2019 7:37 am, edited 5 times in total.

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Calnago
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by Calnago

TobinHatesYou wrote:
Calnago wrote:
Thu Jun 06, 2019 6:57 am
So... the dates again, and how late are they?

Even If I knew the dates, I wouldn't tell you. I fail to see how it's even relevant to the topic.
It’s only relevant in the sense that you keep implying the new Domane is or will be late. Unless they’ve publicly announced a release date, and missed it, then they’re not late. Unless you want to use your “predictions” as to when they “should have” released a new version in the world according to THY.
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TobinHatesYou
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by TobinHatesYou

Calnago wrote:
Thu Jun 06, 2019 7:16 am

It’s only relevant in the sense that you keep implying the new Domane is or will be late. Unless they’ve publicly announced a release date, and missed it, then they’re not late. Unless you want to use your “predictions” as to when they “should have” released a new version in the world according to THY.

Got it, a lame semantics internet argument. Whatever, man, you win.

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