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  1. #1
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    Help buying cranks?

    I recently changed my pedals and stripped my right crank. I took it to a local LBS and tried tapping it to no avail. Now my question is how do I find the proper cranks for my bike? I mostly ride it to work and back (in a city, no trails) and go on 15-20 mile long rides during the weekend. (also, no trails)

    Here is my bike:
    http://www.specialized.com/us/en/bc/...Id=0&gold_ses=

    I know how to change the crank, I just don't know how to do determine the proper sizing. The one thing I do know about my cranks right now are that the length is 175mm, which is very comfortable for me.

    Thanks in advance for any replies!

  2. #2
    Ha ha ha ha ha giantcfr1's Avatar
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    Well the details are on the site you linked. Square taper etc, under technical specs.

  3. #3
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    Yes, I know this but regarding the bracket size I have to find cranks that are 68x118? When I'm looking online I'm not seeing a bracket size on the specs for cranks. I'm fairly new to all of this so I was looking for advice on a good set of cranks to buy as well.

  4. #4
    Senior Member Deathly Hallows's Avatar
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    If you're only replacing the crank, any square taper crank will fit. If the arm length and gearing on your old crank were comfortable for you, it's probably best to look for the same in a new crank. The 68x118 refers to the bottom bracket, not the actual crank itself; if you want to change the bottom bracket as well, you will need the same size. After replacing the crank, you will probably need to adjust the front derailleur (lots of people seem to miss that for some reason).

  5. #5
    Pug
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    High Modulus Pug's Avatar
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    I bent a crank arm on my hybrid and replaced the stock Shimano crank with this one from FSA. It's heavy, but for the price I can't complain. It also worked fine with the existing FD.

  6. #6
    Senior Member Bill Kapaun's Avatar
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    The 118mm dimension is the spindle length of the Bottom Bracket (BB).

    A new BB is only about $15-30, depending on quality, so even if your new cranks require a different length, it's not that big of a deal. Especially if you are buying expensive cranks!

    When you search for cranks, they often specify the required BB length.
    The whole idea is to keep the chain line running "straight" between the chain rings and the rear cogs.
    That's obviously only possible in a couple ring/gear combinations.

    In my riding, I tend to use the middle ring and outer gears. I purposely selected a slightly long spindle length because it gives me an "average" better chain line for the gears I use the most.
    Keep in mind, the rear cogs are spaced 5mm apart. Being off 3 or so mm really shouldn't make much difference, assuming you have a "perfect" chain line now.

  7. #7
    Senior Member Bill Kapaun's Avatar
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    You might let us know what type of cranks you need, ie triple, double etc. along with the tooth counts of the chain ring(s).

    What brand/model/year is this bike?

    Are you just looking for the cheapest cranks, or a higher quality level?

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