Bearings in bottom bracket - gritty scrunch noise

petemadoc
petemadoc Posts: 2,331
edited January 2011 in Workshop
Apologies if I use the wrong names for parts etc, bit of a noob mechanic trying to find my way around the bike

So. . . I stripped my bike down the other day to give everything a good clean and re-grease. The problem I found was that after I'd taken the cranks off I could hear a horrible gritty noise when I turned the bit that goes round in the bottom bracket.

My guess is that the bearings need taking out, cleaning and re-greasing. Is this correct, how do I go about it and what grease should I be using?

Tanks

Comments

  • nicklouse
    nicklouse Posts: 50,675
    what is the BB?

    most are not serviceable.

    some reading for you.
    http://www.parktool.com/blog/repair-hel ... m-brackets
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • petemadoc
    petemadoc Posts: 2,331
    nicklouse wrote:
    what is the BB?

    I think it's this one or similar

    fsa-bb-6000-med.jpg
  • dodgy
    dodgy Posts: 2,890
    They can be serviced with care, but it's a bit tricky. I would just replace it, should cost under £30 delivered.
  • nicklouse
    nicklouse Posts: 50,675
    some companies like BETD do a bearing upgrade service for external BBs. but new can be found for about £20.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • petemadoc
    petemadoc Posts: 2,331
    I've only done 2000 miles. Surely you don't replace the BB after this distance?
  • dodgy
    dodgy Posts: 2,890
    I usually get at least 10,000 miles out of Shimano external BBs (yours is also an external BB by the way), so yes, I would be annoyed at only 2000 miles. There are factors to take into account:

    1. Is it a winter / bad weather bike
    2. Do you have mudguards?
    3. Is water getting into the BB area by way of the frame (as opposed to getting past the seals)?

    Also, sometimes components simply break. By the way, I've heard some stories of FSA BBs being a little unreliable on forums, maybe something in it?

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