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  1. #1
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    How important is frame geometry?

    I've been thinking about getting myself a nice steel hardtail for racing some of the mellower XC courses. I have a Giant Anthem X2 that I love, but sometimes I enjoy having that stiffness in the rear.

    That being said, I do currently have a hardtail, but it's an "AM" hardtail. It's a Transition Trans Am and it's currently built up with a 150mm fork. What if I built it up with a 100mm fork? Or better yet, a fork with travel adjust?

    I know it'll end up being a bit heavier than a true xc race hardtail, but other than that, do you guys think I'll run into any problems? BB height? Slack angles? Not as responsive?

    I love the responsiveness and the aggressive position on the Anthem X2. Do you guys think if I dropped the fork on the Transition, I'd get that similar feeling?

    Transition TransAm:
    http://www.transitionbikes.com/Trans...etrySizing.cfm

  2. #2
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    Reputation: the munts's Avatar
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    You're angles are going to end up being steeper with a shorter fork. Cutting the travel by 50mm is going to make it handle real weird. But I'm sure there's someone else who can explain it better than me.

    If you want to race the TransAm, just do it with the proper fork and the geometry its designed around. It might not be the best tool for the job, but you'll have a good time, and that's the important part.
    read KNOBBY MEATS or be sadly ignorant of the mediocrity that is allowed to exist in the interwebs

  3. #3
    ups and downs
    Reputation: rockyuphill's Avatar
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    50mm shorter fork is going to be about 2 degree steeper head angle which wouldn't be a bad thing as 70.5 deg is about normal for an XC hardtail, some frames like the On-One 456 have the ability to be used with 100-150mm fork depending on the riding.

    BUT, have a look at the BB height and seat angle and it gets more complimicated.

    It has a 12.5" BB height, a drop of 2" in fork travel is going to be almost 1" drop at the BB, which might be a bit low, and it also steepens up the seat angle to something like 74.5deg which would be a bit weird when most hardtails run a 73 degree seat tube angle.

    You're better off getting a hardtail frame designed around a 80-100mm fork so the back half of the bike matches the fork travel you'd want to use.
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  4. #4
    And I don't mean the band
    Reputation: VanHalen's Avatar
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    Quote Originally Posted by JHANguyen
    .... but sometimes I enjoy having that stiffness in the rear.....
    Get a bicycle. You will not regret it if you live. --Mark Twain

    BLAWG

  5. #5
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    Quote Originally Posted by VanHalen
    yep..

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