ls01

I am a little confused by this new Standard by Sram. I have a '16 Tarmac that was osbb. It was factory converted to bb30. I have a different Tarmac that had the same treatment and works fantastic. However the '16 is going to be force axs. This uses the new Dub system. So far as I understand all the Dub crankset axels are the same size and the bb creates the interface to whatever frame you have.
So on a bb30 frame I actually need the dub bb30 unit that moves the bearings outside of the frame again. By pressing its bearings and cups into the cups the factory glued into the frame, where the current bearings are now?
So We are moving the bearings outside the bb shell again like the osbb was, the one that creaked and groaned . Am I looking at this right?

smashndash

“Creaking and groaning” has more to do with poor fit and design than whether bearings are inboard or outboard. Otherwise BSA bottom brackets wouldn’t work.

That being said, you’re right that pressing in aluminum cups that only insert 7mm into the frame would create some problems with the moment load the outboard bearings create. Putting load on the outboard bearings would kind of be like jamming a tiny crowbar into the BB shell. Inboard bearings would not have this problem.

The plastic sleeve in DUB BBs is almost certainly just for sealing and not stiffness reasons. Thread together bottom brackets like Praxis, wheels mfg are way better, and will not creak if properly tightened, but it’s still not the stiffest you can get.

I would recommend doing what I do - go with a one piece bottom bracket from BBinfinite or Hambini. Both will be miles stiffer than the stock DUB BB. They’re certainly expensive, but not much more than a thread together, which IMO is the minimum for outboard bearings in a pressfit shell. My opinion is that if you’re building up such an expensive bike, you deserve the peace of mind that comes from having the best BB. The upgrade from SRAM to Hambini is about $150.

EDIT: Wait, never mind. It’s not possible to use a one piece bottom bracket in a BB30 frame with a DUB spindle, unless you use a custom bearing that takes advantage of the 29mm spindle, which 6806 bearings don’t. The sleeve around the bearing would not be able to slip through. So I would recommend a thread-together BB. The moral of the story is that BB30 sucks. PF30 and BB386 are much better, if anyone wants to use BB spec as a criterion for frame selection lol

ls01

That's great, who makes a thread together bb30 dub ? I've been trying to figure this out for a couple days now without much success.

Chi_Z

OSBB creaked because the tolerance was terrible, my S-work roubaix sl3 has super oversized shell, I could easily spin any pressfit cup inside the shell with my hand, in the end had to use high strength retaining compound but the removal was pretty much impossible so the frame kinda turned into a BB30

smashndash

Token Ninja? Search for “Token Ninja DUB bottom bracket BB30” on amazon. Maybe shoot Token an email to verify that’s what you need. I’m really surprised Wheels mfg doesn’t make one. BB30 is still fairly common, though specialized is the main (only?) manufacturer that still clings to it. I would also ask wheels mfg if they could do something for you.

ls01

Smashndash, thanks for the help. I've ordered the sram dub and the token thread together version. I might try the sram first just to see if it works. But then again I might go straight to the Token just to get it over with.

Le Mechanic

I've been using the stock Sram DUB BB that came with my bike. Force AXS crank as well. I've got about 3000 miles on it, and so far, it's been flawless. I've had the opportunity to work on thousands of BB30, press-fit 30 and other BB's known for creaking. In my opinion, the main cause of creaking is a poor installation of the crank into the bottom bracket bearing bores. If there is any room for the spindle to move even just a little side to side, it will creak, pop, make noise, Etc. eventually.
If you're looking for a good aftermarket alternative bottom bracket, I'd highly recommend a 2-piece thread together type (I like the Wheels MFG version) over the 1-piece type. The 1-piece type are generally more of a PITA long term.

Le Mechanic

Wheels MFG makes a DUB compatible BB for pretty much any frame/BB interface
https://wheelsmfg.com/bottom-brackets/sram-dub.html

ls01

If you look at it, for bb30, they sell bearings. Then I would need spacers to take up a considerable amount of space. The dub axel has a machined place for the bearings to ride. The standard width bb30 the bearing falls inside that area. As far as I can tell. I already have a set of these bearings, that's when the confusion started

ls01

I hear ya and I tend to agree. My osbb was horrible. That was factory modified to bb30 standard. It's been great since.
So how comes this dub system. The factory bb moves the bearings outside of the shell, just like the osbb. I have very little faith that this is going to work out well. I like the threaded unit (Token) more. Should at least be stable in its length.

smashndash

As someone who uses and evangelizes one-piece BBs, could you please elaborate on the 1-piece BBs being a PITA? If it’s serious, I’ll stop recommending them.

The fine print on the Wheels mfg site says the bearing kit is only good for 86mm wide direct fit BB shells. Dub cannot do what BB386 spindles do - use a 68mm bearing stance with spacers. It’s funny because I don’t know of a single bike manufacturer that has a 86x42 direct fit BB shell. So I’m not sure who’s buying that.

Specialized apparently is using the SRAM DUB BB30 stuff as OE. So hopefully it isn’t too bad. Considering that neither wheels mfg nor Praxis have touched this, it made me wonder if such a BB is even feasible, the Token notwithstanding. But ceramicspeed also has a thread-together BB30 to DUB BB. So I’m not sure what the hangup is. It may be worth asking.

Le Mechanic

Yes, you are correct. Just replacing the 30mm BB30 bearings with the 29mm id dub bearings wouldn't work because the spindle on the DUB system requires a wider outboard stance. Not sure how difficult it would be to remove that BB30 sleeve, but if you could, you could use the more readily available PF30 to DUB bottom bracket.

ls01

Thank you guys for the clarity on this. It is odd that until you know exactly what to search for you can't find the thread together pieces. I googled the s--t out of dub bb30 and never saw that option. And the pf one piece designs are still an option also. There is one guy showing how to remove the glued in cups and install his press fit thread together bb. Its pricey but if it works when the others fail so be it.
Again, thanks

Le Mechanic

[QUOTE=smashndash;21194618]As someone who uses and evangelizes one-piece BBs, could you please elaborate on the 1-piece BBs being a PITA? If it’s serious, I’ll stop recommending them.


I've dealt with a lot of the BBinfinite BB's. The first issue I had with them was when a local race team had a sponsorship deal with them. The guys at BBinfinite actually came down and installed around 10-15 in a fleet of team bikes, so I would have to assume they were installed as per BBinfinite's recommended best practice?
Anyway, within a year, a couple of the BB shells broke loose from the frame bore and migrated out. Not a huge deal, we just re-bonded them back in place. I have seen 1 other isolated incident of a BB coming unbonded and working it's way out.
The biggest disaster was a couple of months ago. A customer at the shop had a BB30 on a Cannondale synapse that he had a 1-pc shell pressed into the frame to accommodate a 30mm crank??? But it had a weird undersized bb30 OD bearing that failed and basically destroyed the BBinfinite shell. The issue was removing the damaged shell to save the frame. The wall thickness of the shell was super thin and it was a nightmare to get out.
I guess the short version is They're hard to remove when you need to get them out, and sometimes they come out when you don't want them to.

smashndash

Got it. Yeah those two were definitely on my list of concerns when buying. I read one or two reports of BBinfinite wiggling out but I’ve yet to see such a thing happen with Hambini BBs. I’m hoping this just comes down to tolerance issues with BBinfinite or the frames rather than an inherent flaw with the one piece design. Like if your frame shell is oversized to begin with, a one piece is probably a horrible idea. In that case, I would stick to thread-together since those maintain “tension”. I wish all bike shops had the means to measure tolerances precisely so they could prevent these sorts of things beforehand.

ls01

Well after talking things over with my lbs mechanic, I decided to go with the Token unit straight away. We decided it has the best chance of working without issues.
And Just in case. To the people @ Sram. I am very disappointed in you.