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  1. #1
    Kiwi Cyclist NZ_Rida's Avatar
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    Gearing question

    Hello.
    i've got a gearing question (my dirt jump bike, Giant Rhythym) has currently got 39 x 14T gearing on it and i was thinking of changing it because its sucks!!! i need a better gearign combo for street/dirt becuase at the moment my gearing dosen't accelerate that well and I would like better acelleration for the riding i do. the current gearing makes the bike feel slow and slugish which isn't that great.
    thanks,
    Dan
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  2. #2
    Baned. mude's Avatar
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    when you say "dirt jump bike" is that implying you have more then one bmx or more then one bike...

  3. #3
    Kiwi Cyclist NZ_Rida's Avatar
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    I only have one BMX
    My Bikes:

    2005 Marin Northside Trail
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  4. #4
    Senior Member Brian's Avatar
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    Gearing won't make your bike feel sluggish, you're just weak. 39x14 sounds like you're spinning too much and not going anywhere. Do you have a cassette hub?

  5. #5
    Baned. mude's Avatar
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    if you go to www.danscomp.com you can click links to find a gearing chart where you put the number for the chainwheel and for the freewheel/cog and it'll tell you what that ratios good for.

  6. #6
    Senior Member
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    get a 25t, you will accelerate really good

  7. #7
    Senior Member Brian's Avatar
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    Quote Originally Posted by queensrider86
    get a 25t, you will accelerate really good
    Yeah, if he's got 36" tires, that would be great.

  8. #8
    Electrical Hazard
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    39/14 is a pretty standard BMX ratio.
    For every crank revolution, your back tires revolves 2.78x.

    I'm curious as to what kind of dirt jumping you do, that requires a lower gear ratio than that.

  9. #9
    member
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    Probably the kind where he's not pedalling hard enough and is trying to blame it on the gearing.

  10. #10
    Senior Member
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    just get a 25t, it accelerates way better. ask anybody

  11. #11
    Senior Member
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    Quote Originally Posted by queensrider86
    just get a 25t, it accelerates way better. ask anybody
    No dude don't get a 25T sprocket, that won't help you.

    Get a 23T

  12. #12
    I'm switching to quads racersk66's Avatar
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    Quote Originally Posted by bmichaelx
    No dude don't get a 25T sprocket, that won't help you.

    Get a 23T
    HAHA.

  13. #13
    Your Sport Sucks I_Suck_At_BMX's Avatar
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    you have to remember to get a bigger freewheel too.

    23/18 will answer all your accelerating dreams.

  14. #14
    I'm switching to quads racersk66's Avatar
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    Quote Originally Posted by I_Suck_At_BMX
    you have to remember to get a bigger freewheel too.

    23/18 will answer all your accelerating dreams.
    Yeh that should work, should be really good for dirt.

  15. #15
    Your Sport Sucks I_Suck_At_BMX's Avatar
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    Quote Originally Posted by racersk66
    Yeh that should work, should be really good for dirt.

    what do you mean should??, itll definatley work, we're talkin about a 1.27 ratio, theres nothing better.

  16. #16
    I'm switching to quads racersk66's Avatar
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    Quote Originally Posted by I_Suck_At_BMX
    what do you mean should??, itll definatley work, we're talkin about a 1.27 ratio, theres nothing better.
    HAHA

  17. #17
    Dig. KinetikBiker's Avatar
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    if you dont care about size...then go with something like a 41-15...but it will take strenght

    but 39-14 is one of the standard ratios for bmx gearing

    but the others are

    44-16, 41-15, 39-14, 36-13, 33-12, 30-11, 28-10, 25-9, and if you have the new primo hub you could buy there 8t driver and a 23t chain wheel for a 23-8

    but i wouldnt go any smaller then 30-11...becuase the smaller the chainwheel the more pressure and wear you get faster....

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