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  1. #1
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    Downside to a 24 tooth (or smaller) double crank set?

    I have a 24/32/42 triple on my trail bike and I do like my granny gear. I'm shopping for an AM bike and like the idea of a double, but 26/39 or 28/42 seem to be the typical combos, and I'm scared to loose my precious granny. What would be the downside of running 24 or smaller on the front? (I see the Norco Range 3 uses 22/33). Fwiw, I never feel like I need my 42 except maybe on pavement. Thanks!

  2. #2
    Carbon or Commie?
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    What cassettes are these lining up with?

    Total gear range is the important part, not just front OR back tooth count.

    If small chainring get bigger, but the biggest cassette cog got bigger as well, you may not have lost the "granny gear" ratio that you are used to.

  3. #3
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    Yeah, sorry, 11-36. But maybe smaller than 26 up front is not that uncommon and I just haven't looked hard enough... I see the Stumpjumper has 11-36 + 24/38.

  4. #4
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    Stay 11-36 in rear and 22 or 24 up front for granny if you like climbing the technical stuff or have long steep climbs. I tried to go 26 up front for granny and it just doesn't fit my style of riding. Drop the 42, its dead wieght.
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  5. #5
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    Rule of thumb...Try to keep the largest in the rear at least 1.5x the smallest in the front.

    22x34 = 1.55, 24x36 = 1.5, 28x42 = 1.5

  6. #6
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    Quote Originally Posted by barcolounger View Post
    I have a 24/32/42 triple on my trail bike and I do like my granny gear. I'm shopping for an AM bike and like the idea of a double, but 26/39 or 28/42 seem to be the typical combos, and I'm scared to loose my precious granny. What would be the downside of running 24 or smaller on the front? (I see the Norco Range 3 uses 22/33). Fwiw, I never feel like I need my 42 except maybe on pavement. Thanks!
    If you rarely use the 42T, no downsides.

    I have used 36/24 rings on my trail bikes for years.
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  7. #7
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    Shimano used to make a double 22/36.

    I used this gear combo up front on a SRAM drive train without issue. I know a 14 tooth jump is more than the published limit of a lot of front derailleurs but it worked well for me.

  8. #8
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    I run a 24/39 on my xt 2x10. Did not work well with my Stumpy (direct mount front der) but works perfect with my cdale HT (clamp on der).
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  9. #9
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    with 36-11, the best combination is 36/22. Small granny as you want to - I cannot imagine, where highest gear would not be high enough.

  10. #10
    wyrd bi ful rd
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    I use the 42 as a chain tensioner when going down technical areas to prevent the chain from skipping ... maybe you do still need the largest chainring, just that you do not realise it. Try going out on your next 3hr ride without using the largest chainring to see if it works for you.

  11. #11
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    Quote Originally Posted by chinaman View Post
    I use the 42 as a chain tensioner when going down technical areas to prevent the chain from skipping ... maybe you do still need the largest chainring, just that you do not realise it. Try going out on your next 3hr ride without using the largest chainring to see if it works for you.
    Without the 42 tooth you can shorten the chain and that would increase the tension for DH on your middle ring.

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