Viewing 32 posts - 1 through 32 (of 32 total)
  • are all shimano BB's crap?
  • backtothetop
    Free Member

    Ive used shimano bb’s on all my bikes for the past few years mainly beacuse all the bikes ive had have beem shimano equipped from new, however all of them have had multiple replacements when they started creaking and today ive had enough, I took my orange alpine out today for its first ride since the megavalanche and the BB has let me down again. i dont know if its to do with the fact i ride in wet conditions and through all sorts of mud and shit but as soon as it starts creaking it gets replaced.

    what should i replace it with this time, no more shitmano for me,are hope ones worth the money? other options?

    scotroutes
    Full Member

    Most failures I’ve seen seem to be down to poor fitting. My shortest lived Shimano BB was at least two years and several thousand miles old.

    Mackem
    Full Member

    Are you sure it’s the BB creaking?

    Jamie
    Free Member

    Used SLX/XT/105 over the last 8 years.

    Never had an issue, other than natural death (2yrs+)

    sillyoldman
    Full Member

    Creaking doesn’t necessarily mean it’s worn out. Could just need tightened. If the cups are loose, it’ll creak.

    cloudnine
    Free Member

    http://singletrackworld.com/forum/topic/how-long-should-a-shimano-105-bb-last

    Most failures I’ve seen seem to be down to poor fitting.

    How can you mess up tightening 2 bb cups?

    backtothetop
    Free Member

    all mine have been screw in ones and have all been fitted as instructed. cant rally see how one could get that wrong unless you cross thread it/over/under tighten it.

    i dont claim to be a pro bike mechanic so interested to hear if i may of done something wrong there. the latest offering is an xt, previous have been slx.

    backtothetop
    Free Member

    im positive its the left hand cup thats creaking,will strip it down later and double check,i didnt expect this sort of response from you lot as normally any problems i encounter are common.

    JollyGreenGiant
    Free Member

    As you say fitting the bb cups is relatively straightforward . However what are you doing when you fit the cranks and how much preload are you using?

    orangeboy
    Free Member

    It’s easy to pre load the bearing to much which kills them

    br
    Free Member

    All BB’s fail, just some last longer.

    Hope’s are good and I’ve two 6 year old ones.

    Currently though the BB threads are knackered on my HT, so running (consumable) Deore’s.

    alwhit
    Free Member

    Has your bb on the frame been faced properly if not could really destroy any bb you fit

    backtothetop
    Free Member

    i may be tightening the cranks up too much with the plastic end cap (if possible) so will check that, do people still get frames faced? thought that was a thing of the past?

    nick1962
    Free Member

    do people still get frames faced? thought that was a thing of the past?

    Only for people who don’t want to keep replacing their bottom bracket 🙂

    cloudnine
    Free Member

    Cant quite believe that the threads would be out of alignment. Have the threads chased maybe but face the BB??

    ohnohesback
    Free Member

    Sh*mano BBs have always been disposablke items.

    lobby_dosser
    Free Member

    are you fitting them dry?

    andyl
    Free Member

    How can you mess up tightening 2 bb cups?

    Some people can mess up anything.

    I’ll +1 on the most failures are due to poor fitting. Can be either the fitting of the BB itself or the fitting of the crank. Of course poor cleaning can be bad too.

    Nobeerinthefridge
    Free Member

    I reckon most issues are down to the fact that most installation tools are about 12″ long, so people ‘nipping it up’ in reality are way over torquing.

    JohnnyPanic
    Full Member

    Loose chain rings will also cause a creak in time with your pedal strokes so may be worth checking those.

    duner
    Free Member

    had over a year out of my XTR, not a bad price compared to hope etc, and much better than the cheaper shimano ones

    warpcow
    Free Member

    I get at least 18 months out of SLX/XT BBs. Never faced the shell either but I suspect that depends entirely on your frame. I’m pretty careful about fitting: slowly do it up just with fingers until there’s no play in the arms and no more.

    I’ve had creaks from the BB that were due to dirt in silly places rather than siezed bearings.

    hypnotoad
    Free Member

    un55 still going strong for me 🙂

    Northwind
    Full Member

    I usually get about 9 months to a year of constant use in all conditions, which is pretty good imo- better than most wheel bearings etc. Had a Hope, it was a bit better but not massively- maybe a twice the life, 3 times at most. But 4 times the price.

    IMO the real difference is that Hope are more resistant to sideloading, Shimano really can’t deal with it, and everyone overtightens everything on mountain bikes.

    tomd
    Free Member

    My last SLX bottom bracket lasted four months before it rusted up. I’ve had better life out of XT bottom brackets maybe 6months – 1year. Definitely not over tightened or badly fitted. Currently trying a Gusset one to see if that’s any better.

    Northwind
    Full Member

    tomd – Member

    My last SLX bottom bracket lasted four months before it rusted up. I’ve had better life out of XT bottom brackets maybe 6months – 1year

    Same part btw 😉

    backtothetop
    Free Member

    UPDATE: I needed to ride this weekend so just used the creaky BB i had fitted, after an hour or so of constant use it stopped making the horrible noise and was much more user friendly, so a few more rides coming out of it yet.

    coolhandluke
    Free Member

    My Shimano BB’s used to last months. Then I got a Hope.

    Admittedly, I thought the plastic bit with the “O” rings on it was packaging…..

    legend
    Free Member

    This Megavalanche?

    I think all your bearings have earned the right to die

    bomberman
    Free Member

    I had a couple fail on me in a row, realised it was because water was getting into the frame through the seat tube and rusting the bearings. I now have a lump of wax in my seat post and i always turn the bike upside down after washing it to drain any water out. Seems to be helping so far.

    rudedog
    Free Member

    Ive had an xtr bb for over 3 years – its probably done about 1500-2000 miles. It’s deveoped creaks on a couple of occasions but both times it seemed to fix itself after a while.

    hypnotoad
    Free Member

    My good old square taper un55 is still smooth after years of use, I can’t complain.

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