Previous bottom bracket didn’t last too long but I decided to spend a little more. Uberbike bottom bracket with ceramics bearings.

Making an aweful racket now, so they lasted from March till middle of July, 5 months! Less than 500 miles.

Is it worth chucking now bearings in it, or just scrap it and buy a cheapo shimano?

I’d have to say chuck in a Deore for £12 or whatever they cost.

I don’t know if I’m incredibly lucky with BBs or the fancy ones are a waste of money – I only use Shimano HTII, I ride year-round, I have just one bike so nothing to share the load with, I weight 100Kgs, I live in South Wales – by the luck of a lot of people on STW I should be changing them every other week, but they last 2 years or so.

How do you fit them, many people tend to overtighten according to the mechanic in my local bike shop.

Finger tight and back off a little should do it, do tight and you shorten the life of the bearings.

About 5000km on a hope with GXP in it. Fitting the HTII properly and not over tightening?

I assume you mean the preload screw?

Shimano recommend 35-50NM for the cups;

http://si.shimano.com/pdfs/si/SI-1L60A-003-ENG.pdf

Yes, the plastic preload screw should only be very lightly tightened. The two 5mm bolts should be tightened according to the value shown on the sticker on the crank (on new ones, it will come off fairly quickly)

If you want BB’s to last, either don’t ride in the rain / stop them getting doused in manky water / running down the seattube.

Ceramic bearings completely unsuited to BBs – waste of money.

Smother everything in marine grease and reapply often / after each wet ride

As above, most likely down to over tightening. I tend to get very long life out of bottom brackets by going to the effort of slowly applying more preload step by step (semi-fully tightening the crank bolts each time) until no play can be felt, than add a quarter turn to preload slightly. It typically takes around 4 iterations to get it right. This is usually significantly looser than even ‘finger tight’.

It seems like alot of effort but it only adds a few minutes to the entire job.

I have to say old fashioned sealed BB’s lasted way longer than any of the newer offerings.

Surely once you tighten the pedal arm bolts you aren’t doing any preloading?

I wouldn’t have said I overloaded them, but tough to measure 0.7-1.5NM

I’d have to say chuck in a Deore for £12 or whatever they cost.

+1

dovebiker – Member
If you want BB’s to last, either don’t ride in the rain / stop them getting doused in manky water / running down the seattube.

the much maligned designed for sunnny cali SC frame I recently stripped after 4 1/2 years had a nicely designed BB shell that stopped water coming doen from the seat tube/frame into the BB, there was still the oringal grease from installation in there and it’s done some grim wet rides with no TLC, the hop seal look to be doing their job also so it’s completely possible to have something fit for purpose with some thought into the complete design of the system.

daniel_owen_uk – Member
Surely once you tighten the pedal arm bolts you aren’t doing any preloading?

I wouldn’t have said I overloaded them, but tough to measure 0.7-1.5NM
If you have overloaded them by the time you do up the crank bolts then it is permanently bad. It’s such a low torque figure it’s going to cause problems – as said before it’s a design flaw to look for such a low tolerance in something that 9/10 times is going to be done at home.

it’s a design flaw to look for such a low tolerance in something that 9/10 times is going to be done at home.

I’ll bet that 99% are fitted in factories or bike shops. STW home mechanic is not the norm…

Be interesting to see but given the cranks come off for cleaning, chain rings, BB changes etc. it’s a job a lot of people do at home. Be interesting to also see the life span of those who install properly with a measured pre load and thos that don’t. It also relies on the LBS having a nice accurate low measurement torque wrench that they use and the bod in the factory using it properly.

None of which make it a great design really.

I’ve found regular use helps. If you take your bike for a ride once a week any water is sitting in the BB corroding away for 6 days. If you take our for frequent rides any water stuck in there gets redistributed.

I have to say old fashioned sealed BB’s lasted way longer than any of the newer offerings.

I’m still using an XT Octalink bottom bracket from years ago that just refuses to wear out (it’s been used for years on 2 bikes).

I suspect that Shimano didn’t sell that many due to their durability so forced an upgrade to a standard that sold them many more units.

I’ve got 2 bikes and both running Raceface BBs and cranks, the HT is on over 2000 miles this year without issues, rain, dry, mud, XC, turbo, all good.
The FS is on 1000 miles and running sweetly too still.

I don’t know if it’s the system they use of the compression threaded nut on the cranks instead of the Shimano usual method, but i’m having no issues at all with mine.

The gusset ext24 on my commuter is now 4 (5?) years old, this means it’s done something like 20,000 km.

£25, replaceable cartridge bearings.

I got 12 months from the NDS on my Gusset EXT24 and about 24 months from the non-DS. Slapped some Koyo 6805 bearings in and new Race Face x-type top hats and it’s running smooth again with no wobble 🙂

I turn the preload until the cranks have a bit of play in them which is then taken up by tightening the crank bolts. Although I’ve gotten into the habit of turning it too tight in the past trying to get more life out of Shimano when really one of the bearings was probably toast.

Before then Decide XT lasted about 12 months too.

I find MTB BB’s only last me about 12 months of all weather riding, doesn’t matter if I put a cheap or expensive one in.

I now use Deore or similar and swap it for a new one when the bike gets a post winter strip down and cleanup. If I need to do something else on the bike and the cranks are off, I will pick the seals out and refresh the grease but it isn’t worth stressing over for £12 odd a year.

Managed to double the life by storing bike upside down after rides.

Top Tip from Ride On in Rawtenstall.
They also suggested drilling the BB, will get that done before winter.

Most rides are wet and gritty, was getting less than six months, new one has lasted over a year.

Still not convinced, tbh.
Going square taper next time, they just work (for me).

My Raceface one lasted about 1500Km, replaced with a Hope SS which so far has lasted almost 8000Km in just over two years.

It’s been “looked at” three times: once after about a year then I did a full strip down and rebuild of the bike before the HT550 then a service/clean up afterwards. Not gone beyond taking the “top hat” out and cleaning behind it, haven’t taken the seals off or regreased.

The BBs on my Cannondale last forever – three in 8 years and one of those I only changed because the cups had started to discolour.

The frame is BB30 but it has an insert so it accepts a standard 68 mm BB and because of this the BB is almost entirely enclosed. Any water that runs down the seatube goes around the ‘waist’ of the insert and out of the drain hole.

xtr bb,

good sealing. completely non servicable (unlike the deore ones) but last. currently on 18 months of mine and its the longest ive ever had a bb.

I went XTR BB (30 quid from wiggle) when the RaceFace one only lasted 150 miles before the bearings seized in one side and the other was pretty rough. I’m not sure there was much grease in there from new, probably would have lasted longer if I’d packed them with grease from new. The XTR has around 500 miles on it so far and still spinning like new.

Hopes on all our MTBs and I can’t remember the last time one wore out.

Ridden all year, all weather and cleaned with a hose pipe. If the cranks have to come off for whatever reason I’ll have the dust seals off for a clean and regrease, but that’s it. I have drilled drain holes in all the BB shells though, and do grease the mating faces on the centre tube quite heavily, so it’s quite difficult for water to get in that way.

As above – I suspect a lot of people overtighten the end cap. I just push the cranks firmly home by hand, do up the end cap until it’s just biting then back off 1/4 turn. Then do the pinch bolts up.

Swapped them out last night, weirdly the bearings I took out feel smooth as silk in the hand! I suppose it’s hard to tell without load.

New bearings feel perfect no clicking and grinding when pedalling.

Took all the advice, very little amount of preload and greased all mating faces etc.

Will store bike upside down after a wash.

I had a square taper bb that was still going strong after about 14 years of use, it only got replaced what I changed to an Octalink crank.

Just had my first noticeable BB failure – an sram threaded one that served up 210 miles on a new sonder transmitter. Completely ballaxed, as well, not talking about a bit of play, and taking it out the crank spindle looked like it had done 2100 miles. So something amiss there.

Generally though the press fits on my other bikes are fine – even the much maligned BB30s don’t give me any problems, and I like how easy the bearings are to change.