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Always in the wrong gear
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I want to shorten my cranks down to 165mm and I’d love to keep the DUB bb and chainring I have.
in the COVID bikepocalypse, I can find cranks listed as superboost, (but not boost) but based on what I read, SRAM seems to say that the cranks are just cranks, and the real difference is the chainring offset, 6,3 or 0mm offset.
Is there any reason I can’t buy a set of ‘superboost’ GX or XO1 cranks and slap a plain boost (3mm) chainring on it?
I’m already riding DUB cranks, so the 73mm bb and 32t chainring are on the bike.
 

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... Is there any reason I can’t buy a set of ‘superboost’ GX or XO1 cranks and slap a plain boost (3mm) chainring on it?....
Well yes there is a reason, Sram does not make a XO1 in 165mm yet. XX1 does come in 165mm but the chainring mount is Quarq power meter pattern (8 bolts) and I've only seen mtb chainrings for it from one place in Poland, which leaves you screwed if they go out of business.

If you go Superboost GX you will only need a 6mm offset chainring to maintain a 52mm "Boost" chainline.

If can spend $500 I'd go with the xx1 setup. If you can spend $250 I'd wait for GX carbon in 160-165mm in the next couple of year. If you only can spend $150, put your name on waiting list(s) for regular GX cranks and wait a few months.
 

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So I'm totally new and trying to figure this out, Can anyone explain my the non-boost, boost, and super boost difference, or more specific why someone would choose 1 or the other? Is it frame specific? I'm trying to upgrade my NGX Ripmo build with GX cranks and not understanding which one of these I need. I've come across non-boost, boost, and superboost GX Eagle's. Totally confused and would be grateful for some direction with this.
 

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i'm schralping yer thread
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So I'm totally new and trying to figure this out, Can anyone explain my the non-boost, boost, and super boost difference, or more specific why someone would choose 1 or the other? Is it frame specific? I'm trying to upgrade my NGX Ripmo build with GX cranks and not understanding which one of these I need. I've come across non-boost, boost, and superboost GX Eagle's. Totally confused and would be grateful for some direction with this.
It's entirely tied to the rear-axle spacing of the frame. "Regular" is 142mm; "Boost" is 148mm; and "Superboost" is 157mm. For the most part, you don't get to choose which crankset to use though it's possible to make things work with spacers and different offset chainrings.

The current Ripmo is Boost (148mm). I'd stick with that unless you really feel like getting creative.
 

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So I'm totally new and trying to figure this out, Can anyone explain my the non-boost, boost, and super boost difference, or more specific why someone would choose 1 or the other? Is it frame specific? I'm trying to upgrade my NGX Ripmo build with GX cranks and not understanding which one of these I need. I've come across non-boost, boost, and superboost GX Eagle's. Totally confused and would be grateful for some direction with this.
Simple explanation; each crank adds +3mm to the driveline.

Confusion comes that the "normal" chainring is a 3mm offset but they also offer a 0 and 6mm offset so you can add or subtract 3mm from the overall offset.

I am probably wrong but a non-boost crankset is a boost crank with a 6mm offset chainring (rather than a 3mm)
... why someone would choose 1 or the other? ..
As Gee pointed you have no choice, its frame specific but..... because of the 3 different chainring offsets you can use your boost cranks on a superboost frame to save money or to achieve a narrower Q factor (distance between the pedals). Or you could use a Superboost crank on a Boost frame because that was all that was available during a zombie apocalypse and you wanted to ride your new ride now rather than wait 3 months like the OP.
 

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It's entirely tied to the rear-axle spacing of the frame. "Regular" is 142mm; "Boost" is 148mm; and "Superboost" is 157mm. For the most part, you don't get to choose which crankset to use though it's possible to make things work with spacers and different offset chainrings.

The current Ripmo is Boost (148mm). I'd stick with that unless you really feel like getting creative.
Thank you very much. Makes total sense. I would not have correlated it to the rear axle length.
 
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