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  1. #1
    Senior Member powerband's Avatar
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    Converting a Double Chain-ring to a Single - Please Help

    I have an old double-chainring crank set (Sugino Super Custom) that I want to use for my fixed-gear bike. I will be using the smaller chainring (42T), but I want to bring it from the inside of the spider arms to the outside. How can I do this and still retain a straight chain line?

    So far, I don't have a bottom bracket installed in the frame, but should I bring the crank set (with the small chain ring on the outside of the spider arms) in to an LBS and let them figure which bottom bracket would be appropriate? Can the length of the bottom bracket be chosen to allow a straight chain line?

    Any help will be appreciated, since I'm not familiar in this area!

    Cheers.
    Go Hard

  2. #2
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    I'm trying to do the same. Right now I'm either going to use washers to replace to thickness of outer chain ring or just cut off the part that the bolt goes through and use that, which would basically be a square washer.

  3. #3
    Steel snob by accident iwegian's Avatar
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    you could get bmx chainring bolts. i think they're 5mm

  4. #4
    Senior Member powerband's Avatar
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    The original chain-ring bolts are short enough that they'll work. The problem is that when I move the chain ring from inside the spider arms to the outside (purely for aesthetics), this moves the chain ring about 5 to 8 millimeters out. Can I compensate for this displacement by selecting an appropriate (shorter) bottom bracket? I would like to retain the optimal chain alignment.

    Thanks, again.
    Go Hard

  5. #5
    partly metal, partly real sp00ki's Avatar
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    you can only go but so short. similar to issues w/ the RD crankset, the only real way to fix this is by purchasing a rear paul hub. other than that, it's either inside of the spider or a noisy drivetrain.
    Quote Originally Posted by bonechilling View Post
    Road [racing] is one of the only sports where adult men can compete in a non-scholastic setting, so inevitably 8/10 racers are fiercely-competitive nobodies. It's fun as hell, but it's also the foremost refuge of defeated and aging jocks, turned middle-management types.

  6. #6
    Senior Member powerband's Avatar
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    Quote Originally Posted by sp00ki View Post
    you can only go but so short. similar to issues w/ the RD crankset, the only real way to fix this is by purchasing a rear paul hub. other than that, it's either inside of the spider or a noisy drivetrain.
    Thanks, sp00ki. The irony was that I was considering bailing on the old crank set and buy the Sugino RD.

    I guess going on the inside might have to do, then.
    Go Hard

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