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  1. #1
    WTF?
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    iso vs. jis cranks/BB's

    what exactly are the technical differences in terms of taper angle etc.?

    what kinds of cranks/bb's are which and where does campy fit in?

    any and all info would be appreciated. i got a couple sets of Sugino 75's and couple BB's, one FSA ultimax and one cartridge bearing campy road BB, and i shimano 68x107mm (UN???).

    i'm just trying to be a little more informed about what works with what. so please drop all that obscure knowledge on me that's just been collecting dust in your mind.

  2. #2
    Senior Member mattface's Avatar
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    Campy, and some Campy knockoffs including Gipiemme, and older Sugino, and New Miche use ISO.

    Japanese cranks, or really MOST square taper cranks are JIS.

    From what I understand the tapers are similar, but a ISO crank will not seat fully on a JIS taper putting the chainline out a couple of mm, and a JIS crank will sit too deeply on an ISO BB, and possibly bottom out.

  3. #3
    me have long head tube TallRider's Avatar
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    Yup, tapers are similar, but slightly different. Various European makers, namely Campy but some others (e.g., TA of France) use the ISO taper. Phil Wood makes bottom brackets in both tapers. Main diff is that ISO is slightly smaller or narrower. So, as mattface said, ISO cranks won't fully seat on JIS BB spindles, and JIS cranks will bottom out on ISO BB spindles. In practice, either direction of mismatched stuff can work together, but has greater chance of something breaking or stripping.

  4. #4
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    I agree with both of u... the big problem now a days is that its getting harder and harder to find short BB's, Shimano used to have them from 112 all the way thru 105/104 (i have a 107 axle right here) in lenght, so it was easier to mix stuff. I used for years a set of campy track cranks with a jis NJS shimano dura ace BB... but now that its almost imposible to accomplish because shimano is not doing them anymore or because importers do not bring them.. who knows

    Let me see u have a road campy cartridge right? if the lenght is 111 or 112 it wont work.. i mean it will but the chain line will be a little bit off... if it is a 102 just like the new ones... may be is too short (campy 102 road work fine with miche, shimano UN 107 doesnt work with miche, it is too long), but u have to try... all depends of the star... a deeper star needs a longer BB (campy), and the sugino cranks for sure are JIS so who knows... if u have the time to do experiments... go ahead heheh... worse case scenario u'll need to get a BB anyways.

    Shimano just screw up stopping production of dura ace BB's in other sizes... they were better than campy ones. now we have to stick with the brand...

    cya.
    Last edited by ultraman6970; 02-23-06 at 07:16 PM.

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