Driveside race on SRAM DUB press fit BB failed yesterday – most of the bearings have disintegrated. This was fitted at the start of November, and has done 680 miles. Until yesterday hadn’t given any indication of play, noise, wear etc.

The ‘D’ in DUB is supposed to stand for durable?

How long would you expect a Bottom Bracket to last?

FSA PF30 in my “nice bike” lasted 600 miles and one wet XC race, which was what probably killed it.

Uberbikes ceramic lasted the Tour Divide and developed a bit of play.

Shimano BB that came with my SLX cranks 1900km of poor weather/Wales/Bikepacking

Hope stainless BB 25,000 km and counting on commuter.

How long would you expect a Bottom Bracket to last?

Sram – minutes

Hope ceramic PF41, 4500 miles on the summer road bike and still going strong.
Shimano Ultegra screw in on the all weather commuter, 2500 and still going strong.
Hope stainless screw-in on the hard tail, 2800 and still working.
Truvativ something on the cargo bike, 500 dry miles and it threw up its bearings. Now replaced by a Shimano job.

There’s a reason why I remove SRAM drivetrains from my new bikes and replace with Shimano at the earliest opportunity.

Repack sram ones from new unless you only ride in the dry.

Hope ceramic on the road bike – 20,000km and counting
Hope pressfit on FS – 3,000km and counting
Shimano Deore on fat bike – 3,000km
Sram GXP on commuter – 1,000km
Raceface on HT – 1500km (this was the original BB)
Hope stainless steel on the HT – This replaced the Raceface and has had one change of bearings at about the 10,000km mark, new bearings at 7,000km over four years or so and counting.

There might be a pattern above.

If the bikes been ridden in the wet regularly over winter without mudguards, stored away with the bottom bracket shell full of water, then you’ve probably had your money’s worth.

I have a Shimano UN5x that’s been in my commuter for about 8 years, prior to that it was in at least 2 other bikes, probably over 20 years old, so I’d estimate it to have seen about 40-50,000 miles or more. In all weathers. I think the BB in my wife’s bike may possibly be even older. Square taper isn’t just for Christmas…

Just replaced my dub BB this morning. Strava says it’s done 529 miles. It’s been through lot of pretty rubbish slop. Felt it start to go rough two weeks ago, two rides later and it’s squealing and lumpy. Looks as though there is hee haw grease in it now.

Shimano UN73, 20+ years and 40,000+ miles on my commuter bike. It’ll probably outlast me….

Shimano UN73

‘Ooh lah-di-dah, look at me with my fancy hollow axled and slightly lighter BB’.

Show off.

Same shimano octalink bb thats been on my 2005 stumpy HT since I bought the bike. I have no idea how many 000s of miles its done in 16 years and I do not maintain the bike very well at all. I bought a new one when I upgraded other bits thinking the original would be knackered by now, but I have put the original back in and have a brand new as a spare.

As above, depends.

On the road bike the plastic top hats wore out before the bearings.

Off-road, people have been moaning about bearings since mountaimbikes were a thing. A UN72 might have lasted 40,000 miles On a commuter, but I remember them being an annual thing on MTBs.

British winters off-road kill stuff.

680 miles sounds bad. But I bet if you replace it now, it’ll probably last all summer and most of the winter before failing next spring (assuming no jetwashing or degreaser).

RaceFace thing about 6 months/1000 miles

Hope stainless steel about 6000 miles, then replaced bearings, cups still going.

old square taper moved from bike to bike 20+ years old, still smooth.
Hollowtech shimano, one lasted 5 years, I’m still on the second which is 6 years old and fine.

British winters off-road kill stuff.

My commuter regularly gets used off road (the BB was on at least 2 MTBs prior to being installed on the commuter). And seldom cleaned. The amount of much it sees is horrendous. The grinding paste that is to be found on urban roads is pretty destructive, trust me. External type BBs don’t last that long in town.

How long would you expect a Bottom Bracket to last?

The figures posted seem to suggest “as long as a piece of string”. It does seem though that BBs last longer on a commuter bike than an MTB. Who’da thing it?

Depends how hard those miles are I suppose. I think my current gxp bb is about 18 months old and this last winter it’s been dragged through some awful slop. Got a slight clicking now – so either it all just needs to be taken apart and given a good clean / regrease or it’s time to put in the new one I’ve got.

I’m on my 2nd DUB bb at the moment – I didn’t wear the first one out – I just fitted it to a bike I built on the cheap for my nephew with the NX crank I had. Replaced with a new DUB bb about a month and a half ago with a descendant carbon crank. It felt tight when it went in but the cranks now spin unbelievably easily. Not sure if that’s a good thing or a bad thing 🤷‍♂️

All of the above are 73mm threaded BSA bb’s.

My commuter regularly gets used off road. And seldom cleaned. The amount of much it sees is horrendous. The grinding paste that is to be found on urban roads is pretty destructive, trust me. External type BBs don’t last that long in town.

Yea, but I’ve never had to replace brake pads after a single commute, which is a fairly common occourance off-road.

Similarly the external BB on my road bike (the one that wore out the plastic bushings before the bearings) gets used all year round and did 10,000+ miles on the poverty spec FSA bearings.

Isn’t DUB the one where they made the bearings tiny to squeeze in a larger 28.99mm axle? Asking for trouble. That said, 680 miles through winter doesn’t sound terrible. I once had a Deore BB last a week.

 It does seem though that BBs last longer on a commuter bike than an MTB. Who’da thing it?

I think it’s the basic design of square taper and similar with the bearings inboard of the shell and proper sealing. I’ve replaced in 10 years, thousands of miles and 2 bikes worth of commuting.

shimano xt ht 8yrs (second hand) and still going on the the 4 season singlespeed.

It’s an interesting one this. I saw 680miles and thought ‘that doesn’t seem long’ but it really does depend.

not sure all my rides are logged to the right bike but Strava says winter hardtail has done 1000 miles. Generally ride it for about three months through winter, once a week, 20ish miles each time – that’s only 250 miles a year so while the SRAM BB on it did last over 4 or so years, it had probably only done about 800 miles when it was replaced but it only gets used in filth.

The Full sus has a Hope stainless BB that’s been in there over 4 years and is still running well. That bike has done a some 1000’s of miles but not that many of them caked in mud.

My record varies between 12 years and still going for a UN74 and 25 hours for an FSA titanium ISIS one…
All bar the UN74 on the Stinky are now Chris King and Hope and the Hope ones appear to be better.
Oh, and one Dura Ace Octolink one, no idea how old that is but it’s fine

Dunno. The NDS on my Shimano HT2 is starting to grumble now after a few years in all weathers but it’s still fine. I don’t wash my bike though- just a quick wipe down if it’s really bad before I put it away- which might help with the longevity of the BB.

Sram – minutes

This, unless you’re particularly lucky. Think I got under six months with the one which came with the bike. Press fit shimano was a fair bit better – a year and 3,500 miles. Now put in a Wheels Manufacturing screw-together one which should do as well if not better before it needs new bearings.

Powerspline bb just replaced on my fs. About 400 miles. But that’s 2 winters and lots of wet rides. I used the hardtail a lot last summer due to lockdown. This is a calibre sentry and the Facebook owners group is full of people replacing it with a dub and new cranks. If I were to change cranks I’d fit shimano every time
Hope bb I bought in 2006 had to replace the bearings in about 2014 I think. Third frame by then.

As said above – it depends on what type of BB it is, the quality of it and what kind of conditions it’s ridden in. That aside, I’ve always thought that the bearings for 30 mm cranks and sram DUB cranks in 41 mm shell diameter PF BB’s are just too small and weedy to last a decent amount of time (regardless of the quality of the BB).

The quality of BBs fitted to off the peg bikes are usually poor as they are ‘unseen’ and a prime part for the manufacturers to save money on. The plastic Shimano RS500 PF BB in my Norco Search XR A1 lasted 159 (mostly road) miles before the drive side cup failed and started creaking and walking in the BB shell. The drive side cup pretty much fell out of the frame when I took the cranks off, it had broken into about 3 pieces. Baffles me why you would make a BB from plastic?!

I run 24 mm axle diameter cranks and Hope BBs on all my bikes (41 mm diameter PF and BSA threaded BBs) as the bearings are bigger, last longer and can be replaced without taking the cups out of the frame. Yes, Hope BBs are expensive – but i’d rather have a long lasting, reliable product and not have to go through the faff of replacing BBs regularly.

Yes, Hope BBs are expensive – but i’d rather have a long lasting, reliable product and not have to go through the faff of replacing BBs regularly.

It’s not that much faff on a non PF.
My hope bearings lasted well but it was too much faff to find new ones cheaper than a Saint BB.
I expect a year or so out of the Saint in which time I just need to find a pair of hope bearings cheaper than £15 (based on best price being £19 EACH that seems unlikely) given that and the fact I bought 2x Saint BB’s it seems likely it will get replaced by another non SLX/XT/XTR Shimano one… (which necessitates a new BB tool)

1000s of miles on my nice road bike. I normally get more than one season out of them.

My CX record is one race, so about 50 minutes. Probably 16km.

I’ve had bikes before that collect water in the bb area. Every time I took the cranks off there would be water in the floor. This killed my bearings. I drilled a small hole to let the water out which made a big difference.

I have a hope ceramic bb that’s on its 4th bike and well over 10000 miles. 1 tourer and 3 MTBs. I do remove, clean, regrease regularly.

The other thing to think about, is the bb square? Is it the correct size? Misalignment can destroy bbs.

My gxp is still super smooth 18 months after install on my most used bike. I was expecting it to last a year max given all the stories but it’s been excellent. Shimano last forever. Pf30 a year max unless you only ride in the dust.

Mine all have either XT in or Gusset EXT24s with replacable bearings, none of them are amazing but they all last long enough that I don’t really know how long they last.

I think when I last had a SRAM BB was the last time I had a BB that was so poor I actually knew how old it was when it died.

1629 miles & 4 years on my original SRAM GXP BSA in my Aeris. I do generally only ride it in the dry though.

Square taper isn’t just for Christmas…

My Token square taper BB was on my bike for 6 months and when I took it off it was very rough to turn by hand. Now on an FSA Pro so see how that goes.

Do sometimes miss proper old square taper, the sort where it was kind of terrifying when you did eventually have to change them because they’d be basically welded into the frame by age.

Do sometimes miss proper old square taper, the sort where it was kind of terrifying when you did eventually have to change them because they’d be basically welded into the frame by age.

To quote someone on here, square tapers last so long that they really make themselves at home, and the difficulty of getting them out is not helped a terrible tool interface. HTII solves this problem in two ways….

I’ll raise you a UN91 Dura Ace sealed catridge BB – nearly 30 years. Also a similar age Ultegra UN7? Perfic.

I’ve come to the conclusion that BB life is completely random. The square taper cup and cone campagnolo bottom bracket on my fixie has never been opened and done multiple winters and is the most perfect I’ve ever owned. The pressfit sram GXP on my old roadie outlived the bike and did around 20,000 miles over 6 years in all conditions. The race face cinch on my trail bike lasted about 2 years, a hope one on another bike only a few months (very disappointing given how good the headsets are), Shimano hollowtech BBs anywhwere from a couple of months to a year. The shortest lived was an Acros MTB bottom bracket which lasted one event but in it’s defence it was a winter 24hr race in apocalyptic conditions.