[Closed] Bottom brackets which last more than a handful of rides?

Hope

I'm on my 2nd winter (and the summer) so far with a 2nd hand Chris King.

I get quite a bit longer than you out of shimano though, I think the least I've had is 8 months, the longest about 2 years, are you sure you're not pre-loading them too much?

Got a Hope ceramic BB here that's done quite a few muddy miles since January. I regreased the bearings just this week, one was fairly dry & the other was ok. The seals went back on ok so I think I'll check/regrease them every six months from now on. I seem to recall not being able to regrease Shimano BBs in the past as I couldn't get the seals off without breaking them.

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User fitting error.

I've got 2 shimano HT2's in at the moment, one Deore & one XT, the XT is two years old & Deore 5 months without any problems.
They get jet washed, ridden in lots of wet sand & grit (Sherwood Pines & Peak District)
I'd be inclined to agree with druidh on this one.

HT2 shimano bearings lasted nearly 10,000 miles over a year and a half of abuse. wet/ muddy/ hub deep puddles ect.. as long as you dont let them go rusty they should last..

sounds like the alloy cups could be out of alignment / frame may need facing square again?

ramming a load of marine grease into HT2 bearings seems to help a lot IME, as does not overdoing the preload

mind, my ss is on an octalink bb that's probably 2yrs old now and you can't access the bearings in that (I did try to grease the outside as much as I could, as a sort of shield but I'd guess that's long gone)

sounds like the alloy cups could be out of alignment / frame may need facing square again?

This.

My winter HT is entering it's 4th season of water, muck & filth on the same XT BB.

I don't really [i]get[/i] BB facing - surely the orientation of the cups is down to the orientation of the threads on cups and shell. If the end of the shell isn't perpendicularly cut, wouldn't the cup just sit funny rather than warping to conform to fit snug against it ?

I'm wondering if I should be concerned that a) I cant even remember what BB I fitted to my bike, and b) it was fitted 10 years ago (6 of those years it was on a break in my shed - but its had a good 5 years worth of all terrain riding!)

😳

OK any tips on correctly fitting an HT2 BB? Could well be the answer as I've had similar problems on various bikes over the years.

Although not sure you can preload / overload an FSA BB with a Truvativ chainset as you just tighten the bolt up to the stop?

I don't really get BB facing - surely the orientation of the cups is down to the orientation of the threads on cups and shell. If the end of the shell isn't perpendicularly cut, wouldn't the cup just sit funny rather than warping to conform to fit snug against it ?

You'd be amazed how much force the threads on a BB can take, certainly more than it takes to hammer a comparably sized headset cup on the piss.

And usualy the faceing tool has taps to chase the threads on both sides of the BB shell, so the threads should come out aligned perfectly with the cut faces, or at least better than when you started if it really is on the piss.

I don't really get BB facing - surely the orientation of the cups is down to the orientation of the threads on cups and shell. If the end of the shell isn't perpendicularly cut, wouldn't the cup just sit funny rather than warping to conform to fit snug against it ?

You'd be surprise, especially as the effect can be masked by the spacers - it really doesn't take much to take bearings outside their tolerances.

I was told the best way to ruin a Shimano BB was to overdo the preload, apparently just nip it up. I've got a year old saint that's still perfect despite all the water/sand/mud.

Buy a Hope,

Both my hopes are on their second frame, 5 years old and zero maintenance.

Don't do them up too tight they just need to be gently nipped up, you don't want to squash your balls

Struggling here 😳

And usualy the faceing tool has taps to chase the threads on both sides of the BB shell, so the threads should come out aligned perfectly with the cut faces, or at least better than when you started if it really is on the piss

You saying it'll recut a new thread into an already threaded shell ? SOunds like there'd be insufficient material left there to leave it useable afterwards, especially if the fault was only a few degrees out - wouldn't you just remove all the "wall" of the old thread ?

You'd be surprise, especially as the effect can be masked by the spacers - it really doesn't take much to take bearings outside their tolerances.

SO "all" that deformation must occur prety much right at the interface of the threaded bit of the cup and the "collar" ? Why don't the cups just rip to pieces at that point ? Surely alu's not that elastic ?

Addit: ... and should I be tightening the cups that hard (sufficient to deform them) in the 1st place ?

Hope one is lasting ages for me. I use almost zero preload too (as in their fitting video).

I've had an SRAM one on my road bike for 2 years thats been fine through some very wet weather.

Shimano Deore didn't last long.

XT was better.

(i've never had a frame faced either)

yes you have it right, the alloy cup will deform if the faces are not square, only a tiny bit, but its enough..
the thread cutting is just to clean up the thread and make sure all the threads are in contact with each other (not just one, making the others stretch)

deep groove rolling bearings need to be aligned within 0.2 of a degree before the service life starts reducing..

http://www.skf.com/portal/skf/home/products?maincatalogue=1&lang=en&newlink=1_1_10