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  1. #1
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    Pairing Chainrings

    In the process of putting together the right drivetrain (for me) - just don't need 22-32-44. Going 2x9.

    I don't need the Granny: F22/R32
    I don't need the other end: F44/R11

    So, I'm thinking the cassette stays, I'd drop 2-4 teeth on the big ring, e.g. 40/42 and 4 teeth on the small (formerly middle) ring, e.g. 28.

    But I'm assuming the boys at Shimano gave this some thought - the pairing of the rings? The "timing" of the ramps, the gap from a 32 to a 44? Or, can I just put what ever I want, dial in the deraileur and all's well?

    Thanks and sorry if this is a repost... or a rererepost - damn there's a lot of talk of 2x9
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  2. #2
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    This is kind of a bad news/good news issue.
    The bad news is that it's unlikely that you'll find paired or phased rings in this combination with the ramps on the outer positioned where you need them for hyperglide type shifting. Correctly paired rings generally only come in the common combinations used on new bikes, because that's where the volume is. You might also find that, depending on the crankset BCD, you'll need to use the middle & granny positions in order to accommodate the 28t ring.

    The good news is you can buy non ramped/gated rings and use them exactly the way you want. You'll have some loss of shifting smoothness, but it won't be a big deal. After all, we lived fine for years without phased shifting in the front.

    BTW- if the number of teeth on the inner ring doesn't divide by the number of mounting bolts, you can somewhat phase it by rotating trial and error to find the orientation with the smoothest shifting.
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  3. #3
    Nouveau Retrogrouch SuperModerator
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    Quote Originally Posted by OldZaskar
    In the process of putting together the right drivetrain (for me) - just don't need 22-32-44. Going 2x9.

    I don't need the Granny: F22/R32
    I don't need the other end: F44/R11

    So, I'm thinking the cassette stays, I'd drop 2-4 teeth on the big ring, e.g. 40/42 and 4 teeth on the small (formerly middle) ring, e.g. 28.

    But I'm assuming the boys at Shimano gave this some thought - the pairing of the rings? The "timing" of the ramps, the gap from a 32 to a 44? Or, can I just put what ever I want, dial in the deraileur and all's well?

    Thanks and sorry if this is a repost... or a rererepost - damn there's a lot of talk of 2x9
    The inner ring usually does not have or need ramps or pins to "improve" shifting.
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  4. #4
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    Quote Originally Posted by OldZaskar
    In the process of putting together the right drivetrain (for me) - just don't need 22-32-44. Going 2x9.

    I don't need the Granny: F22/R32
    I don't need the other end: F44/R11

    So, I'm thinking the cassette stays, I'd drop 2-4 teeth on the big ring, e.g. 40/42 and 4 teeth on the small (formerly middle) ring, e.g. 28.

    But I'm assuming the boys at Shimano gave this some thought - the pairing of the rings? The "timing" of the ramps, the gap from a 32 to a 44? Or, can I just put what ever I want, dial in the deraileur and all's well?

    Thanks and sorry if this is a repost... or a rererepost - damn there's a lot of talk of 2x9

    Go read some of the shimano tech docs, basically FDs are rated by the difference in the number of teeth.....

    An FD needs a certain minimum number of teeth difference to work....

    So if you have 44 32 that is a drop of 12 so if you go to 40 you should go to 28....(obivously there is some flexibility in the metric).

    You will have to adjust the height of the FD downwards....

    At some point the FD middle shift bump won't line up with the second ring....

    Then you need to go to a granny middle set-up....

  5. #5
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    Look at a gear chart. If you do not need the 44-11, go with a 36 "middle-as-big" ring which is just about a 44-13. A 24 granny goes well with it. Gives great shifting, at least with Blackspire pro rings I have been using. Very few fit problems as well. Once you start getting to a 26 or 28 granny and 40-42 middle, chainstay fit starts to come into play.

    G
    You can't depend on honest answers from dependant hands...

  6. #6
    Nouveau Retrogrouch SuperModerator
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    Quote Originally Posted by jeffscott
    Go read some of the shimano tech docs, basically FDs are rated by the difference in the number of teeth.....

    An FD needs a certain minimum number of teeth difference to work....

    So if you have 44 32 that is a drop of 12 so if you go to 40 you should go to 28....(obivously there is some flexibility in the metric).

    You will have to adjust the height of the FD downwards....

    At some point the FD middle shift bump won't line up with the second ring....

    Then you need to go to a granny middle set-up....
    The actual functional range is MUCH greater. You can adjust most FDs to work with 34/28 or 45/24.
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