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Just bought a new to me frame that came fitted with a GXP boost bb. Looking for groupsets to fit and there seems to be limited availability of boost GXP sets, but plenty of DUB. Have I been caught in the obsolescence whirlpool already? It's only a 2018 frame! I don't really want to replace the BB before I've even started, especially as it's push fit, so I don't have the tools yet.
Just about all grpupsets will come with a bb so worst case is a swap, all sram still comes in gxp doesn't it?
GXP has been superseded by DUB. Plenty of bargains around though I suspect.
Still readily available despite being superseded by DUB by the looks of it - https://www.chainreactioncycles.com/sram-gx-eagle-12sp-groupset-gxp/rp-prod161511
I think there were bargains, but now sold out. If anyone has a relevant PSA please feel free to share! GX eagle GXP boost groupsets with 170mm cranks preferred.
GXP crank/groupsets just need a boost chainring to make them Boost.
Not sure there's such a thing as a boost bottom bracket, certainly not for GXP
Try this link:
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F163116828444
I got one of these for a hardtail build I did - truvativ is also made by sram and I prefer the graphics compared to the sram branded one.
Also look for a truvativ descendant cranks in gxp as they are also pretty good.
https://www.sram.com/sram/mountain/products/gx-eagle-crankset
not a bargain link but it's a current standard
If you end up with a chainset that's GXP and the BB needs replacing you can always get a Hope BB with GXP converters. That's exactly what I've got as the Hope bearings are loads better than the garbage sram gxp ones.
As above, I run a gxp carbon crankset which I like, I run a Uberbike Ceramic BB which is OK but when it dies I will run a hope BB with the adapter. No need to change cranksets that way
You do realise Sram's company motto is: "Inventing unwanted standards so you don't have to.".
The only BBs I've come across worse than Sram GXP are those from RaceFace.
Every "standard" is on its way out from before it hits the shops these days.
Built in obsolescence in everything.
Maybe I'm just a mardy old git but it all feels quite wasteful and unnecessary (except from a marketing bs point of view).
Back OT I'd second the Hope press fit BB. I've got a pf30 to 24mm axle version and it's a fine bit of kit. My first set of bearings didn't last well but I think that may have been putting the bike away wet and dirty and then not riding for 3 months. Second set have been fine.
So if the general consensus is that GXP is not that good, has DUB been around long enough to show if it's any better?
They had some very well priced (from rrp at least) gxp Eagle boost cranks on bike-discount.de earlier today
https://www.bike-discount.de/en/buy/sram-x1-eagle-carbon-gxp-boost-crank-30t-175mm-841029
And a few others.
They had some very well priced (from rrp at least) gxp Eagle boost cranks on bike-discount.de earlier today
https://www.bike-discount.de/en/buy/sram-x1-eagle-carbon-gxp-boost-crank-30t-175mm-841029
And a few others.
SRAM are a little bit sneaky with these, if you're buying a carbon crank expecting them to be a good weight saving, I think the X1's weigh more than the GX Eagle arms. Same goes (or close) for the Descendant carbon arms.
The only ones that are actually a decent weight saving are the X01 & XX1 arms.
As Hob Nob says above, don't expect a massive weight saving from the X1/Stylo/Descendant (they're all pretty much the same as far as I understand) carbon cranks. I swapped from X1 alloy arms to Stylos and saved about 50g, also switched the DUB GX cranks I bought for the Soul to carbon GXP Descendants and there was even less in it. For me though, there is one reason why I went for the carbon arms; they won't look shite after one ride like both alloy sets did!!!
Standard GXP BB's are a bit pants, but there are loads of decent aftermarket options for both PF BB's and threaded shells. If you have a GXP fitted, buy some GXP cranks, run the BB into the ground and then replace with Hope. Job done.
So if the general consensus is that GXP is not that good,
There is nothing wrong with it as a standard or design, much prefer it to ht2 and had hope converted bb's running for years.
So if the general consensus is that GXP is not that good
Mostly issues from years ago, spread around by Internet & word of mouth, plus issues from not reading the instructions or using a torque wrench properly, with a good helping of "just buy Hope" without a good reason.
Never have issues with GXP. Fitted properly, they last plenty long enough for me, and they're £20 BBs anyway vs £80 Hope that might be last a little bit longer or maybe not.
On gxp I’ve had one bb that lasted about a year and a half and was then a bit gritty (not so I’d notice when riding) and the other is coming up for 2 years old - it came on my Bird Aeris and is now on my hardtail that’s been getting some muddy abuse all over winter. Still
seems ok.
Maybe I’m not that hard on bb’s?
Last year for me - fitted a GXP BB according to instructions on my commuter and it lasted about 1000km. Complete garbage!
Compare with "just buy Hope": I've a Hope BB on my hardtail that's lasted 13,000km and is still going strong with sod all maintenance. By my reckoning (and your prices) that's £260 vs £80. The price of trust is worth much more than that.
The 'problem' with Hope BBs and GXP is that the SRAM system is designed around the non-DS bearing being located with a circlip into the BB shell. The crank axle then clamps around the non-DS bearing and this handles all the side loading with the DS bearing effectively floating (there is a few mm to allow for frame tolerances and chain devices etc).
On the Hope conversion, the crank axle clamps around the non-ds bearing as with SRAM, but the bearing isn't held in place with a circlip and can move under side loads until the DS crank pushes against DS bearing. I've also found on one Hope GXP setup I had to use about 1 million lb/ft to remove an annoying bit of play!
I've had a Hope BB with GXP conversion on for years and it hasn't missed a beat.
GXP is just a Normal/ Shimano BB with a smaller internal diameter on one cup. No reason at all for it to be worse than anything else.
I'm conflicted, usually I hate the redundant standards thing but GXP was always pointless and shit, and so close to being a standard 24mm BB that it was really like having your nose rubbed in it. So it can get in the bin frankly.
But on the other hand, ****ING BOOST. It's like I'm cheering on Hitler because he's killed Pol Pot.
Hob Nob
Member
SRAM are a little bit sneaky with these, if you’re buying a carbon crank expecting them to be a good weight saving, I think the X1’s weigh more than the GX Eagle arms. Same goes (or close) for the Descendant carbon arms.
I think the Descendant's supposed to be strong like ox, rather than light. Whether it actually is or not I have no clue but it can't be worse than a raceface carbon
GXP is just a Normal/ Shimano BB with a smaller internal diameter on one cup. No reason at all for it to be worse than anything else.
Ah but it's not. It has no facility for lateral preload like a Shimano. On GXP, the NDS axle clamps the NDS bearing, to stop lateral movement, but there isn't any preload on the DS bearing so the axle simply floats on that bearing. That's fine when new but after a while, when play/movement develops, there's no way to adjust it out. So creaks and whatnot are terminal. I've jettisoned GXP for that reason. Bad design.
I think the X1’s weigh more than the GX Eagle arms. Same goes (or close) for the Descendant carbon arms.
I don't know for the arms alone but for the same chainrings which should be equivalent :
Gxe: 613g
X1/Descendent Carbon: 543g