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  1. #1
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    external bottom bracket bearing toast need help

    please help. I tried search and I failed.

    One side is locked up and the other feels like gravel. This happened after a few rides in bad mud & rain. I did not pressure wash it, just some light hose sprinkles and light bristle brushing is all. so why are these bearings already toasted? there are not many miles on this bike: its a 2010 stumpjumper comp. am I not allowed to ride in the mud and rain?

    Question: are all these outer bearing cups the same? can just order any shimano cup? The componet listing from Specialized for my bike is "custom shimano integrated" or "shimano FC-M542" ...HUH?

    Just a search on Jenson and I'm finding this: should I get XT? or??? thanks in advance... also attached pics of the bearing on my bike.

    http://www.jensonusa.com/store/produ...g+Bb+Htii.aspx

    pics of my bike:



  2. #2
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    Just my own experience and opinion only, others may disagree with my opinion.
    The seals in the original Shimano BB system doesn't work very well, the plastic "top hat' just takes up room and is a pain to remove with out breaking, if you are trying to re-pack the bearings.
    I suggest you replace the bearings only, there is no need to buy new BB cups. I suggest buying Enduro bearings, they go for about $15 a pair and their sealing system is a lot better than Shimano. The balls in the bearings are bigger also. I've always taken the cups out to replace the bearings, other perhaps have replaced the bearings with the cups in the frame.. Too bad you don't live closer (Southern New Mexico, God's Country), or I'd say bring it over and I'd show you how to do the job. I also suggest when you get the new bearings you pry the seals up with a pin or a small sewing needle, and add more bearing grease. Good luck with that!
    Training on Hills Builds Character, That's How I Got To Be One!

  3. #3
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    hey thanks for the tip. I got the bearing out at work today and found it is #6805

    found them on Amazon for $6... but shipping may be a week or more.
    http://www.amazon.com/ABI-Enduro-car.../dp/B001GSSHZ0

    but I went ahead and ordered the XT complete cups for $40 from Jenson because they can be at my front door tomorrow. I will also order bearings for the other cups and just have them for backup when the shimano ones take a dump again. and yes I said "when" not "if"


  4. #4
    usually cranky
    Reputation: b-kul's Avatar
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    yes, it is just a matter of when. any bb designed for shimano hollow tech ll will work. i think the superstar bb's look intresting, they use balls that are like 4x bigger.

  5. #5
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    Searched eh? Missed the 2nd sticky?
    Outboard Bearing Bottom Bracket Service Guide. With Pics.

  6. #6
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    Quote Originally Posted by hatake
    I started reading that but the bearing doesn't need lube it needs replacement. and I didn't know if all shimano were the same or not. I'm re-reading it now. and I see there is more info in it than I thought. but I really don't think that the one seized bearing will come back to life

  7. #7
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    The bearing your showing should have had a flat washer type seal then the dust cap snaps over that. Was it there? It shouldn't have had problems with a ride in wet and mud. It would take time for corrosion to cause damage of the balls and races. Did you try to clean and re-grease?

  8. #8
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    yea, it had the seals and dust cap. I removed it.

    The bike is used, so maybe previous owner had hit it with pressure washer. However, this all happened after two back to back rides in really bad mud. followed by some wet rides in sandy conditions.

    anyhow, it seems like a really premature failure.

  9. #9
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    It sounds like the grit got into the bearings. If they haven't set and corroded you might be able to flush them out with kerosene and then blow them out with air, grease them and be good to go.

  10. #10
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    here's a good website to find p/u the bearings you need.
    http://www.vxb.com/Merchant2/merchant.mvc?
    You may also find these bearings listed as a part # 61805-2RS

  11. #11
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    I have had a better luck with Shimano bearings, especially XTR 960 bearings were really good, having very durable seals. I started to say that bearings in XT has no seals on bearings facing inside (not sure why), that if water gets in the frame, and if the inner plastic tubes are not tight, then it WILL fail sooner than later.

  12. #12
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    The previous owner may not have used a pressure washer. Mine started grinding a couple rides after I took it through some deep creek crossings. They're good as new after following the sticky directions.

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