24mm Bottom Bracket Recommendation

[bucknejo]

hi guys

in the course of pivot bolt maintenance on my FS I also decided to pull out the cranks and low and behold observed what appears to be a chip on the drive side of the bottom bracket cup. my intuition tells me this shouldn't be there, but idk - is this normal?

anywho - if this is a problem, then i'm guessing it has to be replaced, and no, i'm not going to light the whole thing on fire. do you know how long it takes to get a bike these days? rhetorical question.

i believe the current BB is 24mm 68/73 BSA Shimano MT800 which is holding my SRAM GXP style carbon crank. i'd like to not have to worry about something like this again so maybe there's something that's more bullet proof? any recommendations?

is this overkill? https://chrisking.com/products/bottom-bracket-threadfit-24

 

[ItsWin]

Looks like the chip is on the plastic dust cover which can be easily replaced.

If you don't want to mess with that plastic dust cover in the future you can replace the drive side bearing with a 2437 (dimensions: 24x27x7mm) bearing. Here's an example of one that works:

24 x 37 x 7 440C Stainless Angular Contact Bearing

Bearings are sold individually and not in pairs. SMRA2437LLB BEARING NOTE: THIS IS A SPECIAL ANGULAR CONTACT BEARING DESIGNED FOR BOTTOM BRACKETS RUNNING

www.enduroforkseals.com

If you need to replace BOTH bearings there's a kit available for GXP style BBs:

SRAM GXP 440C STAINLESS STEEL BEARING KIT, ANGULAR

Angular Contact 440C Stainless Steel bearing kit replaces bearings is SRAM GXP bottom brackets. Works for GXP outboard bottom brackets, GXP press-fit (

www.enduroforkseals.com

If you don't have the specific tools needed to replace the bearings you can have your shop do it.

 

[stb222]

For a cheaper BB, I wouldnt worry about just replacing the bearing and shields, would just get a new one. You can always go with the standard Sram one for cheap.

I have a 24mm chris king bb and I am not sure it is worth the money. That being said, it looks super nice and is relatively easy to service and the bearings get better with age. If you are looking for bling, just get this: https://www.kogel.cc/collections/sr...b-gxp-for-sram-gxp-cranks?variant=34790522122

I think wheels manufacturing BB's are really hard to beat from a cost to durability perspective. Keep in mine that GXP (sram) is 22 mm on the non drive side which most BB's just have a plastic sleeve to account for this. In any case, get the GXP specific one.

Wheels Mfg - BSA Threaded Bottom Brackets

Wheels Mfg BSA threaded bottom brackets, tools and replacement parts.

wheelsmfg.com

You can either get the normal ABEC 3 bearing or the angular contact bearings. For the extra $21, I would go with the ACB's.

 

[Ryan.P]

Pretty sure that's normal for shimano bb , if it spins smooth don't worry about it save money for something else

 

[bucknejo]

Pretty sure that's normal for shimano bb , if it spins smooth don't worry about it save money for something else

so two things:

• I realized the current bb installed is a gxp bb, not shimano. the bb is actually a 100mm fat bike bb on my 68mm shell so I guess I have to understand how that got in there and if this really makes a difference
• I ended up buying another gxp bb for like $30 and yes, it has the same chip so I'm guessing this is a feature not a bug.

on another note, I did find the problem for which I suspected the bb. it turned out to be a coned-like washer that was reversed in the top linkage.... so long story short - I'm not going to install the new bb until I really have to which will probably be when I bring the thing to the LBS over the winter for a full service.

thanks for all the feedback, may the force be with you.