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Discussion Starter · #1 ·
So my bike has a Dub BB92 pressfit bottom bracket. I wanted to upgrade it to maybe a Chris King. Question what should I be looking for when I purchase a new BB. The crank has a 30mm spindle. Will a PF30 work? I’ve searched the Internet without really getting a straight answer
 

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Elitest thrill junkie
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You can use a 30mm axle crank, but it is not the best combo due to the BB bearings being too small. Hope/RWC make a BB92 bottom bracket that fits 30mm spindle cranks with double row bearings and they are decent IME. The standard race face and sram BB for this is poor. The new SRAM DUB crank spindles do leave just enough space for the bearings, so you should be good with any DUB BB92 bottom bracket. BB92 was designed for the shimano 24mm spindle, not 30mm, which is the source of most of the issues. The bike manufacturers knew this, but speced 30mm cranks anyway, because race face next SL was so light it would make the bike lighter and more competitive, at the cost of bearing durability.
 

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So my bike has a Dub BB92 pressfit bottom bracket. I wanted to upgrade it to maybe a Chris King. Question what should I be looking for when I purchase a new BB. The crank has a 30mm spindle. Will a PF30 work? I've searched the Internet without really getting a straight answer
You've got a lot going on and I'm not sure you gave all the necessary info.

First, you say your crank has a 30mm spindle. Is this a new crank? Or did it work with the Dub BB? This is important.

Second, the BB92 standard was designed around a 24mm spindle. The old SRAM GXP worked well for this, too. Anything else is a bit of a kludge. GOOD bottom brackets for this fitment are sorta uncommon. There's really only one out there, and it's sold by a few manufacturers. Enduro, Hope, e13, wheels, etc.

https://wheelsmfg.com/bottom-brackets/bb86-for-30mm.html
https://www.endurobearingsonline.co...ntain-bike-bottom-brackets/products/bb86-4130
https://www.hopetech.com/products/drivetrain/bottom-bracket/press-fit-41-30mm-bottom-bracket/
https://bythehive.com/products/press-fit-bottom-brackets

DO NOT buy the RaceFace PF 41 30 bb. I used one once (before all of these were available on the market) and it was grindy trash in probably 1/4 of the mileage. I've been using the bb sold by Enduro with steel bearings.

You have 3 basic dimensions you have to work within as your constraints.
1. bb shell diameter. If your frame has a BB92/DUB bb in it now, then that shell is 41mm in diameter. Nothing else will fit. PF30 requires a 46mm bb shell.
2. Spindle diameter. Pretty self explanatory.
3. Shell width. BB92 shells (or more accurately, PF41 shells), in particular, can be found in multiple widths. The original is 92mm wide, the same width as a 73mm threaded shell plus bb cups. You'll see them in fatbike widths, too. Originally, mfrs called them PF41 shells, with xxx width. Now, they're using consistent terminology with the original standard and calling them BB121 or BB131 (less common). It honestly doesn't really matter for the most part. It's really only relevant for the ones that have a plastic sleeve between the cups inside the shell, for protection against water. And even the sleeves mostly aren't necessary.

So, Chris King doesn't make a bottom bracket for this fitment. Probably never will because it's a kludge anyway.
 

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Discussion Starter · #4 ·
So the cranks on my bike are the SRAM x1 crank. I’m finding out these were only available to manufactures and not sold separate. I’m just assuming it’s a 30mm spindle but I might be mistaking. The crank is what came on the bike from Yeti
 

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So the cranks on my bike are the SRAM x1 crank. I'm finding out these were only available to manufactures and not sold separate. I'm just assuming it's a 30mm spindle but I might be mistaking. The crank is what came on the bike from Yeti
DO NOT ASSUME!

If your bb is DUB, then so are your cranks if they all came together. That is NOT the same spindle diameter as 30mm! It's smaller. When SRAM introduced DUB, they started phasing out both 24mm and 30mm spindles. Put those cranks on a 30mm bb and they will wobble. you MUST use a DUB bb. It is new enough that there are not many aftermarket options.
 

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Discussion Starter · #6 ·
DO NOT ASSUME!

If your bb is DUB, then so are your cranks if they all came together. That is NOT the same spindle diameter as 30mm! It's smaller. When SRAM introduced DUB, they started phasing out both 24mm and 30mm spindles. Put those cranks on a 30mm bb and they will wobble. you MUST use a DUB bb. It is new enough that there are not many aftermarket options.
Thank you so much. I was just looking for something a little higher quality and that would last longer. I will look for another OEM SRAM Dub BB92
 

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Think about going with a Shimano BB and Shimano crank. Goes with the BB92 like cookies and milk. I think its a great setup and I've never had a problem with it.
 

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Evidently RF makes a few different ones. I just ordered the dual row external seal version. I guess I'll find out how well it lasts me.
This is the one I had. it sucked.

https://www.raceface.com/products/details/cinch-bb92-bb

The only "other" bb92 bb that raceface shows on their website is the x-type one, for 24mm spindles.

Is this what you bought? Odd that it's on jensonusa, but not RF's own website. Curious if it'll be notably better than the one above.

https://www.jensonusa.com/Race-Face-30mm-Double-Row-Bottom-Bracket

Think about going with a Shimano BB and Shimano crank. Goes with the BB92 like cookies and milk. I think its a great setup and I've never had a problem with it.
good idea, but not always an option.

In my case, I have a fatbike that uses a PF41/BB121 bottom bracket. Shimano doesn't make a single crank that fits it. So SRAM GXP was the only option for a smaller spindle crank when I bought it. RaceFace introduced a compatible Aeffect crank awhile after I bought it that would work well, too. But when I bought the bike, my options were pretty limited. And now that SRAM is killing GXP, that reduces the number of available cranks available new for such bikes that don't make big compromises on bottom brackets.

I hope frame manufacturers start dumping bb92 shells.
 

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Elitest thrill junkie
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I'll just give my usual advice - buy a set of digital calipers and measure your stuff. Now you know what you have.
So many other uses for these too, one of the best things I have bought...
 

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For RF 30mm spindle BB92s I find four, permutations of single vs double row, with or without external seal:

BB92 Bottom Bracket: 41mm ID x 92mm Shell x 30mm Spindle, Double Row Bearing, External Seal
BB92 Double Row Bearing Bottom Bracket: 41mm ID x 92mm BB Shell x 30mm Spindle
BB92 Bottom Bracket: 41mm ID x 92mm Shell x 30mm Spindle, External Seal
BB92 Bottom Bracket: 41mm ID x 92mm BB Shell x 30mm Spindle
 
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