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  1. #1
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    SRAM PF30 BB - Incredible amount of drag

    Anyone else found that this BB has an unreasonable amount of drag? I've triple-checked the bearing tension and even with the collar backed all the way off, the bearings are really stiff. Feels like they're packed with molasses. Will it loosen up with time? Are there reasonably priced alternatives that are better?

    This is on a Jet9 RDO that I took a lot of care to build up light for racing, and I can't help feeling that this BB is robbing a lot of power.

  2. #2
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    I have the same feeling on my Stumpjumper with PF30 and S-Works crankset. I think it all seal drag in my case, because I have sprayed a thin lube the seal its much better. I hope someone has found a fix or a BB that works better. If not, Chris King is shipping their PF30 BB in the very near future.

  3. #3
    arrogant sandbagger
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    Have you ridden it yet?

    I have no experience with PF30 but my GXP BBs would not even complete a rotation in the stand when I spun them. They all loosened up within a ride. In fact, I remember seeing a video explaining sram BB/crank installation which said exactly that.

  4. #4
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    I have several hours on mine, they did not loosen up. The PF30 is very different set up compared to GXP and that being said my actual BB is the Specialized brand which is different (slightly) than the Sram.

  5. #5
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    I've only got a couple hours on it, so I guess I'll keep riding it for a while. Was curious if other people found they loosened up over time.

  6. #6
    thecentralscrutinizer
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    I don't notice it when riding which makes me beleive it's just the seals.
    2014 Giant Anthem 27.5
    2013 DeVinci Leo SL
    2009 SE Racing SoCal Flyer
    2008 SE Racing lil Ripper
    2003 TiSport Gman

  7. #7
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    Quote Originally Posted by spsoon View Post
    Anyone else found that this BB has an unreasonable amount of drag? I've triple-checked the bearing tension and even with the collar backed all the way off, the bearings are really stiff. Feels like they're packed with molasses. Will it loosen up with time? Are there reasonably priced alternatives that are better?
    Same here. I just installed the SRAM PF30 on my steel frame cross bike. There is a huge amount of drag. It seems to be beyond reasonable for seal drag. I only have about three hours on the BB from a ride yesterday.
    The WW forum has posts about mis-alignment of the bearing cups and someone else talked about polishing the spindle to get it to insert more freely.
    I checked my set up and the bearings are smooth.

  8. #8
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    To update the thread, I've got maybe 30 hours on mine now and it has loosened up considerably. A good flick of the wrist will now spin it about 3-4 revolutions with the chain off. I think the grease the bearings come packed with just needs to be loosened up with some use.

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