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Thread: BB size??

  1. #1
    RoadRash
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    BB size??

    I have a shwinn world sport that i converted to a fixed gear,a dn i just picked up some new cranks, now I need your guys help on how to find a proper size BB for square taper cranks, any help would be appreciated. here is a pic of the bike.

  2. #2
    What? Carbon Based's Avatar
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    what brand/model are the cranks?

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    RoadRash
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    sugino Xd

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    Villainous huerro's Avatar
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    New Sugino xd needs a 107 according to this:

    http://www.benscycle.net/index.php?m...181da72ab25b15

  5. #5
    RoadRash
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    But what diameter and will a 107 give me a decent chainline? or is that stuff usually is standard.

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    roll'em high shants's Avatar
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    you'll need a standard english (68mm) bottom bracket in whichever length. since you say you need 107mm, get a Shimano UN-54 107mm cartridge unit. they are cheap and do the job quite well.

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    kind ot but im converting the same bike... did you have any trouble with the rear dropouts being so short?

  8. #8
    RoadRash
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    nope no issue with drop outs.

  9. #9
    Villainous huerro's Avatar
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    Quote Originally Posted by VwFix View Post
    But what diameter and will a 107 give me a decent chainline? or is that stuff usually is standard.
    68mm is standard for American, Japanese, and most English bikes and the 107 will give you a 42mm chainline. 42 is pretty standard for track hubs.

    What rear hub are you running?

  10. #10
    . bbattle's Avatar
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    68mm is the diameter of the bottom bracket. 107mm is the length of the crank axle/spindle.
    Most bikes will be 68mm with a 24 tpi (threads per inch) bracket. Also known as the English bracket.

    You can get old style bottom brackets that are cups, ball bearings, and the axle. The axle can be had in different lengths. Axles come with three sections and the middle distance must be the right one for your bottom bracket or the bearings won't be happy.



    As usual, Sheldon Brown has the answers; go check out his website.
    http://sheldonbrown.com/chainline.html
    http://sheldonbrown.com/harris/botto...ets.html#axles
    Last edited by bbattle; 01-23-08 at 07:40 PM.

  11. #11
    fails just as quickly thequickfix's Avatar
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    Quote Originally Posted by bbattle
    68mm is the diameter of the bottom bracket.
    I think you mean bottom bracket shell width.
    Takin' the first bus out of Shell Town

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