1. The most important thing about buying a new bike is to make sure it fits. The only way you'll know if the bike is right for you is to size up the bike and make sure that the bike's geometry matches your body's geometry. Ask questions and do some research.
mtn. biking 101
2. If possible, try to find a shop that will let you demo the bike on real dirt. Five minutes in a parking lot won't cut it. You wouldn't buy a car without a real world test drive, and a bike should be no different.
3. Don't belive the hype. Just because your favorite rider or best friend rides a certain bike, that doesn't mean that's the best one for you. Have an open mind and be realistic about your needs and ability.
Results 1 to 9 of 9
  1. #1
    mtbr member
    Reputation:
    Join Date
    Feb 2012
    Posts
    11

    Isis bottom bracket overhaul

    So I pulled this bottom bracket out of a frame I recently bought. I think its been in there a while, my guess years. It seems alright though, still spins, but it is a little rough. If I can I definately want to salvage it cause I'm on a tight budget with a DH build I'm doing. So I want to over haul it, take it apart, clean it, lube it and put it back together. The problem is I don't know where to start, what to take off first since I cant get anything to budge and there aren't any nuts and bolts. I am not bad with mechanics but this one has got me. Any one got any suggestions as to how to break this thing apart? The crank side cup is still on it, but I don't know if it is fixed on there or if it is supposed to come off just like the other one. It drives me crazy when I know something comes apart but cant figure out how to do it, so any tips would help.
    Thanks.
    Attached Thumbnails Attached Thumbnails Isis bottom bracket overhaul-bottom-bracket.jpg  


  2. #2
    mtbr member
    Reputation: winter's Avatar
    Join Date
    Nov 2009
    Posts
    331
    Looks like you have a cartridge style bottom bracket, these are not designed to be user serviceable. Some of the heavy duty cartridge style bottom brackets have 3 bearings (2 drive side and 1 non-drive side) and others have 4 bearings, you might be able to pry off the dust seal and flush out the old grease with some WD40 and then repack with fresh grease, but good luck getting at the inboard bearings. As long as the bottom bracket doesn't lock up and doesn't allow your cranks to wiggle and hit the chainstays, then it's probably okay to put it back on the frame for some more action.

    My memory is a bit fuzzy, but I don't believe the threaded cup on the drive side of Truvativ bottom brackets were removable.
    Go on ahead, I'm gonna take a breather.

  3. #3
    LightJunction.com
    Reputation: lightjunction's Avatar
    Join Date
    May 2011
    Posts
    774
    He's right. Those bearings are pressed into place, and they're cartridge bearings (read: unserviceable). As long as there isn't play in the bearings (ie: your cranks don't wiggle from side to side, as stated by winter), I'd re-install that bottom bracket and keep riding it.
    We sell quality bike headlights and flashlights.
    www.LightJunction.com

  4. #4
    Sweep the leg!
    Reputation: Caffeine Powered's Avatar
    Join Date
    Mar 2005
    Posts
    3,824
    Quote Originally Posted by winter View Post
    My memory is a bit fuzzy, but I don't believe the threaded cup on the drive side of Truvativ bottom brackets were removable.
    Not correct. That would mean the frame manufacturer machined that part of the BB and you'd be stuck with that type or brand of BB. The drive side cup is removable with the correct tool.
    Authorities speculate that speed may have been a factor. They are also holding gravity and inertia for questioning.

  5. #5
    mtbr member
    Reputation: oldskoolbiker's Avatar
    Join Date
    Jun 2005
    Posts
    1,600
    You do know the drive side cup is reverse threaded right?

  6. #6
    mtbr member
    Reputation:
    Join Date
    Feb 2012
    Posts
    11
    Yes I found that out when I was pulling it off the frame. I got a hunch when it wouldn't budge when I was tryin to go lefty loosy with it.

  7. #7
    Former Bike Wrench
    Reputation: mtnbiker72's Avatar
    Join Date
    Jan 2007
    Posts
    15,985
    The bearings can be replaced with the right tool, but it's probably cheaper just to buy a new BB

    Truvativ Giga Pipe Team DH Bottom Bracket 2011 at Price Point

  8. #8
    mtbr member
    Reputation: bikerjohn64's Avatar
    Join Date
    Feb 2012
    Posts
    162
    Those cartridge bearings like other posters has mentioned are not fully serviceable. The sealed cartridge bearings inside are pressed in during manufacturing and even if you could remove the other threaded flange; you will be faced with exactly the same as the other side that is exposed. If you are feeling some roughness in the spindle; it's only a matter of time (unfortunately) before you will need to replace it.
    Maybe if you go into you LBS with "hat-in-hand" (and you BB) and ask if they may have a used one (in better condition) in the back somewhere that you could "buy" ; they may sell it?

  9. #9
    jbf
    jbf is offline
    mtbr member
    Reputation: jbf's Avatar
    Join Date
    Jan 2004
    Posts
    292
    Buy an SKF ISIS bottom bracket. Its the only bulletproof ISIS bottom bracket I have found.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •