need a new one – anything other than sram under £30 worth buying?

oxymoron do one.

pmsl – not

An interesting link but a lot of rude language.

Just stock up on SRAM ones and a tool when you see them cheap.

HT2 bb with a £3 shim off ebay.

Good and cheap don’t usually go hand in hand. Invest in a Hope BB and GXP adapter then you’ll only ever need to by replacement bearings when they, eventually, need replacing.

Hope and GXP adaptor as above

I’ve just fitted an Uberbike one, seems good so far.

Uberbike, you can replace the bearings easily with a hope bb bearing tool.

Wheelsmfg

I’ve bought the eBay shim to allow me to use shimano bbs. Job appears to be jobbed.

Praxis BB – Great quality.

https://www.tweekscycles.com/uk/praxis-works-sram-gxp-threaded-bottom-bracket-upgpr-68-0301/?istCompanyId=56f52ebf-49f3-492a-9cbb-cb6ab0fc1bf0&istFeedId=33b89177-5114-4491-9c2a-09a3a7cb23b2&istItemId=wqtllwwwq&istBid=t&gclid=EAIaIQobChMImKfsnerY5QIVhbTtCh1YPQx5EAQYASABEgLO1fD_BwE&gclsrc=aw.ds

is there not an issue with the way that shimano BBS need to be pre loaded whereas the sram chainset won’t do that?

Yep. Praxis. 18 months and 7500 km and still going strong.

I’ve bought the eBay shim to allow me to use shimano bbs. Job appears to be jobbed

This.

Hope bb + adapter.

My uberbike one was toss.

is there not an issue with the way that shimano BBS need to be pre loaded whereas the sram chainset won’t do that?

I think that Shimano BBs use radial bearings, so you should end up with the same arrangement as a GXP BB where the NDS bearing is fixed on the axle, and the DS is floating. If they’re angular contact bearings then I think that the lack of preload would be a problem.

The GXP bearings on my CX bike have just died again. Going to give these a try:

https://www.ebay.co.uk/itm/133016731085

The problem with HT2 + top hat spacer for GXP is that there’s no adjustment for axial load as the non-drive crank is tightened firmly against the stepped spindle. You need something to take up the slop i.e. wavy washers and or BB spacers but if you overload them you’ll kill the bearings in no time.

I think that Shimano BBs use radial bearings, so you should end up with the same arrangement as a GXP BB where the NDS bearing is fixed on the axle, and the DS is floating. If they’re angular contact bearings then I think that the lack of preload would be a problem.

They’re a sort of hybrid IIRC. An ACB, but the races wrap around like a radial bearing. Which is why you can’t get radial bearings to fit in the shells.

The standard 68/73mm SRAM BB’s seem to last just fine for me, got >1000miles out of it on the singlespeed before a freak rock killed it (slate drainage bar in the path at an angle, hopped over it and landed between crank and frame).

Hope + addapter on the fat bike though as theres more clearance and the top hat falls out of the SRAM BB, and the bearings out of any aftermarket one that doesn’t have a circlip. The hope plastic shiled acts as a circlip but needs replacing (or rotating to the non drive side) every so often.

Stock GXP Team. Last me a good few years these days and cheap at £20-30.

Never see why people have problems unless they’re not tightening the crank bolt enough.

Though I still also put an o-ring on the drive side in the space between crank face and the dust cap, but they seem to stay in place better now.

I only have GXP on my CX bike, and they last about as long as you’d expect given what they suffer.

The video above makes some interesting points about the problems with GXP, which I think can be summarised as a) SRAM engineering tolerances are shoddy, so the NDS crank may not actually clamp the bearing b) the bearing arrangement is common in industry, but is not well suited to the changing radial load that a crankset sees. He claims 20% more friction than the Shimano arrangement, although I’m not sure where that figure comes from.

My Wheels Mfg one was 4 years old and still going strong when I sold the bike it was in.

No complaints.

The problem with HT2 + top hat spacer for GXP is that there’s no adjustment for axial load as the non-drive crank is tightened firmly against the stepped spindle. You need something to take up the slop i.e. wavy washers and or BB spacers but if you overload them you’ll kill the bearings in no time.

There is no need for anyh axial load per se with not-angular bearings like standard Shimano or Hope ones. On standard HT II the preload is only there to prevent sideways movement of the cranks, which is not going to be a problem with GXP (whether with a 22mm id nds bearing or a 24mm one with top hats). On non-Hope, non-Shimano types you will need a wavy washer on the ds to keep the external seal against the face of the cup. This is not needed with a Hope BB cup as the labyrinth seal can’t come out of its groove. Not sure if the Shimano thin plastic top-hat thing needs holding in place that way.

Just get some Shimano cranks.