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Does ANYBODY maybe have the complete BB30 standard? Apparently the splined spindle-to-crank interface is standardised, but it's impossible to find any data on it. The only thing available on the official site is the BB shell specification for frame builders.
https://www.qbp.com/diagrams/newsite/tech_product/sram/compatibility-map-dub-choosing-an-mtb-bottom-bracket.pdf
https://www.qbp.com/diagrams/newsite/tech_product/sram/dub-choose-a-road-bottom-bracket-compatibility-map.pdf
Those help?
Not even close.
BB30
Shell width will measure 68mm (road) or 73mm (mountain)
Shell inner diameter (ID) will measure 42mm; BB30 bearings have a corresponding outer diameter (OD) of 42mm
Bearings press directly into the frame and stop at removable snap rings; two snap ring grooves will be present inside the shell
Designed for BB30 30mm spindle cranksets; adaptors are available that permit the use of 24mm spindle cranksets (i.e. Hollowtech II, GXP)
Not quite sure what you mean. BB30 is a pretty much seen as a BB standard, not a crank standard.
Spindle to crank interface? There are many different BB30 compatible cranks, all with different constructions.
Are you looking for the specific Cannondale crank info?
@Whattheheel "The only thing available on the official site is the BB shell specification for frame builders." from my first post. I'm looking for info on the spindle, not how to mount the bearings.
@dirty booger
https://www.bb30standard.com/wp_super_faq/as-a-frame-or-crank-manufactu…
"As a frame or crank manufacturer,"
There are also cranks available not only from Cannondale, but Specialized, Sram, Rotor and FSA (and RF Next SL apparently) that all use mostly the exact same splined interface and are, judging by some random forum posts, compatible between each other as well. And DUB also looks to be a downsized BB30 spindle interface as well.
Also: https://stagescycling.com/en_us/content/understanding-spindles
"While the splined portion of 30mm spindles (the hollow section that connects the left and right sides of a crankset) is a standardized design,"
All the info that I can find points to the fact that it was at some point standardised and released, but there isn't any info available online (who would have thought, the internet does forget).
Definitely not standardized for BB30, only in the length between bearings and bearing race OD.
What you linked from Stages is the SRAM splined spindle interface, which many others use or have used. SRAM would be the best source of info for that.
However, it is pretty poor design in that it requires a massive torque spec to keep the arm from coming loose, and they still often come loose. And if they don't come off by themselves, then you need a breaker bar to get them free. I would stay away from that interface!
BB30 over view:
BB30 Road for 68mm BB shell
BB30 MTB for 73mm BB shell
BB30A for 73mm BB shell the A stands for Asymmetric these are Cannondale specific only, the BB shell on these are made 5mm wider on the non drive-side only. This means the rear hub & drive train are off-center in the frame but the bottom bracket is symmetrical.
BB30-83A for 83mm BB shell is the same as BB30A except these are 83mm width instead of 73mm.
BB30 DH for 83mm BB shell this can only to be found on the Specialized Demo S-Works frame from 2016, it's the only DH bike that is using the BB30 standard.
FWIW, DUB (similar interface to BB30) never came loose for me. And needing the breaker bar kinda negates that too. And the breaker bar is needed because of aluminium to aluminium contact between the spindle and screw galling up, apparently using a steel bolt solves this issue (GXP was all steel after all).
The BB30 crank spindle standard (8 lobe spindle ends, 30mm diameter) was developed by Cannondale for the BB30 bottom bracket standard. Many companies make a variety of length spindles using the same 8 lobe, 30mm spindle. The standard of the ends of the spindle could still be called "BB30" as they were developed for the BB30 application. However, they are ubiquitous on 30mm spindles, and imitated by DUB, so maybe calling it the 30mm spindle standard might be better. Stages makes their spindles because not all manufacturers clock their 8 lobes the same, so it you get a crank arm from SRAM and a crank arm from FSA, they might not be 180 degrees apart when mounted to a spindle.
@Primoz I haven't been able to find any CAD or diagrams of the actual spindles. If I take the time to draw one up I'll pass it on to you.
Modelling it is the easy part. TOlerancing everything for it to fit together reliably is the challenge.
Save you some time modelling it.
https://grabcad.com/library/cannondale-hollowgram-cranks
Someone else's model not mine.
To my knowledge this isn't a published standard, as pointed out it was first used by Cannondale on Hollowgram cranks. To get the tolerancing on these you'll need to measure a bunch of different cranks to find a range.
Turns out the spline is not part of the open standard. Oh well...
That spline has a lineage which I feel makes it the defacto standard. I think it goes back at least as far as the Magic Motorcycles cranks, so it became the CODA standard; FSA made Cannondale's cranks, and it was adopted Sram, Raceface and others, including me (https://www.digitbikes.com/concentric-bb).
Here are the bones of my model:
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