Kona oversize bottom bracket confusion

funkyjams
funkyjams Posts: 19
edited July 2012 in MTB workshop & tech
Hi- I've got a Kona Kula Watt frame which has a shimano BB91-42 bb fitted. I want to fit my older XTR-970 cranks but they are made to fit a wider shell. The BB fits the 24mm shaft Ok, its just the width of the frame shell is too narrow. The frame shell without the BB is around 73mm but it is oversize...
What's the deal!?
Thanks

Comments

  • nicklouse
    nicklouse Posts: 50,675
    Just fit the cranks to the current BB.

    All the info is on Parktools.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • funkyjams
    funkyjams Posts: 19
    But the cranks are way too wide for this BB..?
  • nicklouse
    nicklouse Posts: 50,675
    Add the spacers.

    http://techdocs.shimano.com/media/techd ... 625426.pdf

    There is no difference in the cranks.

    And get a correct width of the BB and state if it is with or without the cups.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • nicklouse
    nicklouse Posts: 50,675
    And what year as 2011 has a BB30 BB.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • nicklouse
    nicklouse Posts: 50,675
    TBH we need pics of what you have.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • funkyjams
    funkyjams Posts: 19
    OK I think I've sussed- the frame is a 73mm diameter BB30. I've bought it from someone who has fitted the BB91 which I've finally worked out...is no good at all.
    I'll get in touch & get it removed.
  • nicklouse
    nicklouse Posts: 50,675
    then have a look at the KCNC BB30 to HT2 adaptor BB.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • funkyjams
    funkyjams Posts: 19
    Yep will do, thanks for your time.
    Someone on another forum has worried me that the frame could be damaged by fitting a BB91- any truth in that?
    cheers
  • nicklouse
    nicklouse Posts: 50,675
    funkyjams wrote:
    Yep will do, thanks for your time.
    Someone on another forum has worried me that the frame could be damaged by fitting a BB91- any truth in that?
    cheers
    i would not have thought so as they have just fitted a smaller set up-

    depends on the cups were they metal or plastic.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • funkyjams
    funkyjams Posts: 19
    Cant really tell as they're in the frame? The rim feels like metal.
    But yes still a 30mm set up I guess..

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