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  1. #1
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    Bottom Bracket help, and yes; I've been to Sheldons

    I think it's just a basic comprehension problem.

    I have a 2008 Fuji Newest 1.0. I'm pretty sure the sound and problems I'm experiencing are coming from the BB. looking to upgrade. It came with the FSA Mega Exo BB and the Omega Crank.

    http://www.fullspeedahead.com/fly.as...layout=product

    2 questions:

    1. The BB, what BB size/style would I need to replace it with for it to fit on the bike?
    2. Is the Omega a decent crank? It doesnt seem to be the problem currently. If i replace the BB, will I be forced to replace the crank?

    Thanks

  2. #2
    Senior Member surreal's Avatar
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    you'll want an external bottom bracket. There are really expensive (and nice) ones made by chris king and phil wood. there are FSA ones, and RaceFace ones that'd work. I recommend getting a shimano 105 or similar; they're compatible and cheap and have been very reliable for me (more so than the race face, and from what you're describing, the FSA version you got might not be all that, either.) SRAM/truvativ bottom brackets are NOT compatible, as the crank's axle (the 2-piece crank's analog to the spindle) is of a wider diameter.

    http://www.treefortbikes.com/eurl.ax...22362937___116

    I don't have any experience with the FSA omega, but you can probably find reviews if you're interested. If it has been a good crank thus far, i wouldn't change it out. You'll need to take it off to replace your BB (make sure you get the proper tool for the BB; hex wrenches are all you'll need for the crank), then put it back on. You can always swap out the crank later, and even run the same BB, even if you switch to a double.

    hth
    -rob

  3. #3
    M_S
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    Also if you get an FSA you need the MegaExo version, which is for their aluminum cranks. The carbon cranks use a different size.

    I second the Shimano recommendation though.

    The Omega is FSA's least expensive external bearing crank I think. I haven't heard good things about the bottom bracket and I can't imagine the rings are anything special, but probably the only thing you'd benefit from by replacing the arms themselves is weight. I wouldn't bother. An entry to mid range bike which would come with an Omega probably has other things on it where your money would be better spent upgrading.

  4. #4
    AEO
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    I'm pretty sure you can use shimano bottom brackets with FSA mega exo cranks, as they're both the same axle size.
    the only thing you have to change are the amount of spacers you use, as mega exo cranks are spaced out for 73mm shells. a 68mm BB shell will use 5mm of spacers with a mega exo BB to take up the slack.

    The shimano system and bearing seals are far superior to mega exo, GXP and campy external cups, that's for sure.
    campy and GXP are not fully interchangable with the cheaper GXP or shimano external BB cup systems.

    sram/truvativ GXP right side cup is interchangable with shimano, but the left side is special and requires the GXP cup, and obviously needs spacers to correct length.

    I think, right now, you can buy 105 cranks off of ebay for $75+S&H
    Last edited by AEO; 12-06-10 at 09:49 PM.
    Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
    http://sanfrancisco.ibtimes.com/arti...ger-photos.htm

  5. #5
    Senior Member peripatetic's Avatar
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    If the cranks are fine, seems unnecessary and wasteful to replace them along with the bb. At the least, you can swap in a new bb and see if that's sufficient for you to feel the bike's ride-able and safe again.

  6. #6
    Slacker ZippyThePinhead's Avatar
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    Dunno what sort of noise you were experiencing, but I was getting a creaking sound from my FSA BB, and my bike only has 600 miles on it.

    My mechanic friend took off the left crank and found the splines on the spindle were completely dry. Water had worked its way in, and there was a bit of mineral residue/corrosion on the splines. He greased the spindle, reassembled the crank, and the noise is gone.

  7. #7
    cab horn
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    Quote Originally Posted by AEO View Post
    I'm pretty sure you can use shimano bottom brackets with FSA mega exo cranks, as they're both the same axle size.
    the only thing you have to change are the amount of spacers you use, as mega exo cranks are spaced out for 73mm shells. a 68mm BB shell will use 5mm of spacers with a mega exo BB to take up the slack.

    The shimano system and bearing seals are far superior to mega exo, GXP and campy external cups, that's for sure.
    campy and GXP are not fully interchangable with the cheaper GXP or shimano external BB cup systems.

    sram/truvativ GXP right side cup is interchangable with shimano, but the left side is special and requires the GXP cup, and obviously needs spacers to correct length.

    I think, right now, you can buy 105 cranks off of ebay for $75+S&H
    Dude, stop posting wrong things on this forum.

    Seriously

    1) Shimano BB's will only work for a very small selection of FSA cranksets. There's a reason why FSA makes half a dozen BB's for all their different cranks - becuase they're different.
    2) Omega uses the CK-C4000 FSA bb
    Mes compaingnons cui j'amoie et cui j'aim,... Me di, chanson.

  8. #8
    cab horn
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    Quote Originally Posted by ZippyThePinhead View Post
    Dunno what sort of noise you were experiencing, but I was getting a creaking sound from my FSA BB, and my bike only has 600 miles on it.

    My mechanic friend took off the left crank and found the splines on the spindle were completely dry. Water had worked its way in, and there was a bit of mineral residue/corrosion on the splines. He greased the spindle, reassembled the crank, and the noise is gone.
    Let's hope those weren't carbon crank splines. That requires loctite 641.
    Mes compaingnons cui j'amoie et cui j'aim,... Me di, chanson.

  9. #9
    AEO
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    Quote Originally Posted by operator View Post
    Dude, stop posting wrong things on this forum.

    Seriously

    1) Shimano BB's will only work for a very small selection of FSA cranksets. There's a reason why FSA makes half a dozen BB's for all their different cranks - becuase they're different.
    2) Omega uses the CK-C4000 FSA bb
    the FSA part? yeah, they do have more than one type of bottom bracket and spindle diameter.
    But I'm correct on the GXP part, I measured it, tried it, and it does work with the correct amount of spacers.

    Why FSA would make it complicated is beyond me. They pulled the same thing campy did with square taper for low and high end cranks.
    Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
    http://sanfrancisco.ibtimes.com/arti...ger-photos.htm

  10. #10
    Slacker ZippyThePinhead's Avatar
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    Quote Originally Posted by operator View Post
    Let's hope those weren't carbon crank splines. That requires loctite 641.
    No, the spindle looks to be stainless steel.

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