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Converting PF30

John WhJohn Wh Posts: 239
edited December 2015 in MTB workshop & tech
Well, the PF30 BB did well to last just under 3 months. I went to check the Stumpy over today and the non-drive side bearing had seized.

I managed to free it up and repack the grease, but it's noisy and probably not long for this world.

I've recently been reading up on Wheels Mfg's PF30 to outboard BBs. These seem like a good idea as they are serviceable.

From my understanding though, I will need a new crank with a 24mm diameter spindle to fit the BB. I'm leaning towards mid-range Raceface stuff.

Any suggestions? or if this isn't a good idea? I really don't want to replace the PF30 with the same thing, just so it happens again before winter is out.

Other option is to keep my existing crank and just get a quality BB (Hope or Chris King).


  • JGTRJGTR Posts: 1,404
    My SRAM PF30 just gave up on my Camber after not a great deal of use, from what I've read they are censored so pretty much any other BB will be a vast improvement. I went with the Wheels Manufacturing direct replacement, mainly because it's what my shop recommended, online reviews were ok and it has traditional type bearings which can be replaced for a relatively small cost (DIY job). Haven't ridden it yet, not sure if even notice the difference, hopefully will last longer than the standard BB. Again from what I read the PF30 bearings are service items (ie they rarely last longer than a season) no matter what manufacturer you use so it may be beneficial to look for a more permanent solution as you have, or just be prepared to change the bearings regularly.
  • John WhJohn Wh Posts: 239
    JGTR, I read your thread about it the other day and was thinking that mine had lasted so far :)

    Whatever I end up doing, I'm definitely not getting another standard one.
  • My understanding is that you do have an issue with poor quality bearings in your PF30 BB - I do not quite get how a conversion from a 30-mm-spindle-crankset to a 24-mm-spindle-crankset is linked to that.

    However, if one day the PF30 BB that originally came with my road frame set should be done, I will probably replace it through the Chris King PF30 BB for the following reasons:
    - Judging from my experience with CK hubs & headsets, the CK ball bearings are of very high quality and easily servicable (stainless steel* - so no corrosion issues)
    - The CK design is one of the few PF30 BBs featuring plastic sleeves at the spindle / bearing inner race interface. (This design is tested and tried - see Shimano HT II - and I guess many of the creaking issues of PF30 setups are due to the metal on metal design of most BB30/PF30 BBs.)

    *) The optional 'ceramic' bearings to me seem little value added for a lot of extra money.

    As mentioned, a Wheels Mfg replacement PF30 BB could also solve your problem.
  • RockmonkeySCRockmonkeySC Posts: 15,247
    Chris King isn't worth the cost.
    They're no better quality than Shimano XTR but considerably more expensive.
    The lifetime warranty is a joke as well, they only honour it if you can prove it was fitted and regularly serviced by a Chris King trained mechanic.
  • John WhJohn Wh Posts: 239
    Well, from what I've read the standard Sram PF30 BB is pants. I thought I was going to be the exception, but was proven wrong by a seized non-drive side bearing.

    To be honest, £150 for a BB is quite insane, but I've only ever read good things about CK. If that's the case Rockmonkey, they shouldn't sell them to home mechanics.

    It's interesting you say that though, as I've just received a new bar and stem. When I read the packaging, it clearly states it must be fitted by a qualified mechanic! Seems like a cheap get out clause for warranty issues.

    I'll eek the last few miles out of my current one and probably go for the Wheels Mfg PF30.
  • Chris King isn't worth the cost.
    They're no better quality than Shimano XTR ..

    While I have no intentions to persuade anyone: Number one is a matter of personal preferences (time vs. money). Number two is simply not true. In particular, the stainless steel bearings in my CK headset and CK hubs are still in great shape after more than a decade (with regular maintenance) while the SM-BB90 (XTR thread-in BB cups) do not even last for three years (also with regular maintenance). My experience is that stainless ball bearings do not mind some water intrusion while to ordinary ball bearings corrosion will be the beginning of the end (to come soon).
  • The RookieThe Rookie Posts: 27,747
    So you can compare apples (headsets) with pears (BBs) can you?

    The Headset on my commuter is an original 2006 Carrera one still going strong, making CK overpriced using your ten year parameter, BB's on the other hand need replacing far more often, you don't know how long a CK BB would last as you've not used one it seems.
  • RockmonkeySCRockmonkeySC Posts: 15,247
    I have known someone to have a Chris King bottom bracket last a few months. Chris King wouldn't replace it under their lifetime warranty because he hadn't had it serviced in those few months by a Chris King trained mechanic.
    I pay £30 for an XTR bottom bracket and don't touch it for three years and it's still running smooth. I'd say that's better value and quality.
  • John WhJohn Wh Posts: 239
    To be honest I think the Chris King BB only come with a 5 year warranty, rather than a lifetime. I would be pretty upset if it developed a fault in the first 3-6 months, only to be told that the warranty is void.
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