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BB30a options

bobbydigitalbobbydigital Posts: 251
edited August 2019 in MTB workshop & tech
So I am looking to buy a BB for a Cannondale Jekyll for my friend, it's probably a 2014 and takes press fit BB30a


I read up on BB30a that the A is for Asymmetrical. "The bottom bracket shell is made 5mm wider on the non-drive side only"

I see the bottom brackets advertised as BB30/BB30A, so guessing I can just buy bb30 bb and run that in a bb30a shell?

Posts

  • lemonenemalemonenema Posts: 238
    from cannondale website

    An example of this is the new BB30A found on the Synapse. The "A" stands for Asymmetric - the BB30A adds 5mm to the non-drive side of the BB shell for a wider, stiffer base. To accomodate the wider BB shell, the BB30A gets a longer spindle and the non-drive side crankarm angle is changed to maintain the same Q factor and even out ankle clearance on both sides. Cannondale Hollowgram BB30A cranks will work on both BB30 (68mm BB width) and BB30A (73mm bb width) by changing the non-drive side spacers.
  • Nice one thank you.
  • AlejandrosdogAlejandrosdog Posts: 1,975
    lemonenema wrote:
    from cannondale website

    An example of this is the new BB30A found on the Synapse. The "A" stands for Asymmetric - the BB30A adds 5mm to the non-drive side of the BB shell for a wider, stiffer base. To accomodate the wider BB shell, the BB30A gets a longer spindle and the non-drive side crankarm angle is changed to maintain the same Q factor and even out ankle clearance on both sides. Cannondale Hollowgram BB30A cranks will work on both BB30 (68mm BB width) and BB30A (73mm bb width) by changing the non-drive side spacers.

    This is not an answer to the ops question.
  • JBAJBA Posts: 2,706
    lemonenema wrote:
    from cannondale website

    An example of this is the new BB30A found on the Synapse. The "A" stands for Asymmetric - the BB30A adds 5mm to the non-drive side of the BB shell for a wider, stiffer base. To accomodate the wider BB shell, the BB30A gets a longer spindle and the non-drive side crankarm angle is changed to maintain the same Q factor and even out ankle clearance on both sides. Cannondale Hollowgram BB30A cranks will work on both BB30 (68mm BB width) and BB30A (73mm bb width) by changing the non-drive side spacers.

    This is not an answer to the ops question.

    Yes it is. It confirms that the OP can fit a a BB30 bb as long as he changes the spacers.
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  • AlejandrosdogAlejandrosdog Posts: 1,975
    JBA wrote:
    lemonenema wrote:
    from cannondale website

    An example of this is the new BB30A found on the Synapse. The "A" stands for Asymmetric - the BB30A adds 5mm to the non-drive side of the BB shell for a wider, stiffer base. To accomodate the wider BB shell, the BB30A gets a longer spindle and the non-drive side crankarm angle is changed to maintain the same Q factor and even out ankle clearance on both sides. Cannondale Hollowgram BB30A cranks will work on both BB30 (68mm BB width) and BB30A (73mm bb width) by changing the non-drive side spacers.

    This is not an answer to the ops question.

    Yes it is. It confirms that the OP can fit a a BB30 bb as long as he changes the spacers.

    The information you provided only confirms that pf/bb30a HollowGram cranks can fit in a narrower bottom bracket than it was designed for by adding spacers to pack out the space left by the spindles extra 5mm length.

    The question the op asked was can he buy a standard bb30 bb and fit to a bb30a frame. The answer to that question is that the bb30 standard is direct press into the shell of bearings which are held in the correct place by a circlip so yes just buy some bearings and press them in.

    However some Jekyll frames have the pf30 bb standard, which is a different kettle of fish. In that instance the op should first establish exactly which bottom bracket standard he has. The letters Bb30 or pf30 on a Cannondale frame are not firm indications of the actual bb standard. Eg my evo hi mod says bb30 but actually has a pf30 bb.

    To the op. The difference is that the pf 30 standard involves pressing in plastic/ nylon cups into the frame and the bearings into the cups. There is no retaining clip. Since the diameter of the hole in the frame has to accommodate the cups and the bearings it is larger. The pf30/a standard is well served by aftermarket options to remove creak etc. Look on the wheelsmfring website for further details.
  • gezebogezebo Posts: 364
    I’m not sure if you’ve looked at cannondale spares .con or something but they are very helpful. Particularly when it comes to the slightly different bearing sizes that the headsets have which may be a requirement in the future.
  • AlejandrosdogAlejandrosdog Posts: 1,975
    gezebo wrote:
    I’m not sure if you’ve looked at cannondale spares .con or something but they are very helpful. Particularly when it comes to the slightly different bearing sizes that the headsets have which may be a requirement in the future.
    +1 for cannondale spares, they've always been great for me too.
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