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bottomed out crankset

stefanostefano Posts: 254
edited August 2018 in Workshop
My Miche Primato Advanced crankset has bottomed out on the bottom bracket. I have a Dolan Seta track frame with SKF JIS 107 bottom bracket, as per recommendation of the manufacturer. It also makes a creaking noise on every pedal stroke.

Anyone experience something similar? Shall I go for an 110mm bottom bracket?

Posts

  • cooldadcooldad Posts: 32,599
    What does bottomed out mean?
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  • The RookieThe Rookie Posts: 27,804
    I think they are saying the crank arms have bottomed out (are fouling) the bottom bracket shell, but that's pretty much a guess based on the rather garbled description. I love descriptions were the writer assumes you know a whole raft of detail so they don't bother sharing it with you.

    Example - 'As per recommendation of the manufacturer' - of the frame, BB or cranks?
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • stefanostefano Posts: 254
    By bottomed out I mean the crank arms are touching the bottom bracket cups. i.e. When tighten the bottom bracket bolts the crank arms go so deap on the bottom bracket axle that they get in contact with the bottom bracket cups.
  • Vino'sGhostVino'sGhost Posts: 4,129
    lol from that description, it sounds like youre using cranks designed for a wider bottom bracket shell than you have in the dolan.

    But it's hard to tell from your description
  • imposter2.0imposter2.0 Posts: 11,969
    As far as I'm aware, the Seta has a standard 68mm BB shell, and your Primato chainset seems to be correctly matched with a 107mm JIS BB. In other words, there's no obvious reason why you are having problems. Unless...

    Unless you actually have an ISO BB, not JIS. If that's the case, it might explain why the crank arms are hitting the BB cups, as the (JIS) arms will sit much further inward on an ISO BB than they would on the correct JIS BB.

    If there is any doubt about your current BB, I suggest you bin it and get hold of a correctly-matched Miche 107mm JIS BB and try again. There should be absolutely no reason why the correct chainset and BB should not fit on that frame.
  • Vino'sGhostVino'sGhost Posts: 4,129
    Imposter wrote:
    As far as I'm aware, the Seta has a standard 68mm BB shell, and your Primato chainset seems to be correctly matched with a 107mm JIS BB. In other words, there's no obvious reason why you are having problems. Unless...

    Unless you actually have an ISO BB, not JIS. If that's the case, it might explain why the crank arms are hitting the BB cups, as the (JIS) arms will sit much further inward on an ISO BB than they would on the correct JIS BB.

    If there is any doubt about your current BB, I suggest you bin it and get hold of a correctly-matched Miche 107mm JIS BB and try again. There should be absolutely no reason why the correct chainset and BB should not fit on that frame.

    Ahhh yes its jis I'd forgotten all about jis and square tapers.

    If for any unforeseen reason you have difficulty getting a jis BB get an iso one but dont get the 107mm one (which you might have now,) choose 110 and that will work and give you the correct chainline too.
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