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  1. #1
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    Sep 2012
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    Square Bottom Bracket / Crankset Questions

    Hey all, looking for a little advice. My back-up bike is an older Allez, 2000 Allez A1 Triple, used primarily by friends or when mine it being tuned up. I just took her out for the first time this season and I notice that there is some serious issues with the chainrings, specifically the smallest of the three. They're all pretty worn (the bike's 12 years old), but the smallest seems to have gotten bent somehow. The bike has all of the original parts, chainrings, bottom bracket & crankset included. The way I see it I have a few options, either I replace the chain rings or replace the whole crankset. Truthfully, I'd like to dive in get a new crankset on there, I am not 100% certain that the chain ring is the only part out of whack, part of me worries the crank may have gotten slammed somehow. I've never dropped it or been in a crash with it, my best guess is it got hurt in a move into my new house.

    This is where I need help:

    The bike has a square tapered BB, it moves well, the bearings feel fine and there is no unwanted movements, I worry that perhaps if something hit the bike the BB may be compromised... but it doesnt feel that way. I'm having trouble finding a crankset that seems worth buying that will work with a square bb. Is swapping out my bb for a newer one an option? Is it a good option? Or is there anyone that can suggest a crankset that would work with the current BB? To be safe I can always grab another UN40 to make sure there are not issues in the future.

    Anyway, I know this is a bit verbose, I apologize. Thanks in advance, I appreciate any insights you guys have.

    Edit - Link to my bike with specs
    http://www.bikepedia.com/QuickBike/B...e#.UFNLvlErUxh

  2. #2
    Senior Member
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    The benefits you'll feel JRA from swapping bb is marginal-to-none. Why not pull the crank off, unbolt the ring and straighten it out?

  3. #3
    Senior Member
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    You may be able to straighten the chainring without dismantling anything with a tool such as this: http://www.bicycletool.com/chainringstraightener.aspx

  4. #4
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    I'll rip it apart this week and see how far out of wack the ring is. If this doesn't fix it I'll come find out more about swapping the bottom bracket or replacing the crankset. Thanks!

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