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Thread: Frame flex

  1. #1
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    Frame flex

    I have a new 29er and i am getting a small about of frame flex. about 2-3mm in the rear triangle/bottom bracket.

    is this normal? or some to be worried about?

    I think the frame is alloy 7005

  2. #2
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    How do you know that you have 2-3mm flex what kind of test did you do. It's normal for the frame to give a little. Have you seen time warp. What kind of frame is this?

  3. #3
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    Its a 29er hardtail 7005 alloy

  4. #4
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    [QUOTE=mimi1885]......... Have you seen time warp. .............QUOTE]

    I have, and its the most beautiful thing in the universe. But by the time I saw it, it was over and was beginning again.

  5. #5
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    Op I got that part from your first post, I meant what brand?

    Some brand incorporate flex to the frame as their trade, I've seen Bianchi road bike that built like that, for the rear chainstay a few companies make them flat so it's more vertical compliance but lateral still rigid.

  6. #6
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    Cheap crank arms can flex that much. Your TIRES flex way more than that. 2mm a very insignificant figure.

  7. #7
    Bicyclochondriac.
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    Quote Originally Posted by Grich002
    I have a new 29er and i am getting a small about of frame flex. about 2-3mm in the rear triangle/bottom bracket.
    Measured how and when? When you just sit on it? When you are pedaling? When you lay it on it's side between two saw horses and jump on it in the middle? And what exactly is moving? Are the rear stays twisting? The bb moving side to side (bike basically bending)?
    15mm is a second-best solution to a problem that was already solved.

  8. #8
    "Ride Lots" Eddy Merckx
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    I too am interested to know how you measured the fle so precisely.

    Most people who think they feel flex in a frame are feeling the wheels and/or tires. You cannot accurately compare the flex of two frames unless ALL the other components are exactly the same. This is one of the reasons most bike reviews are utter crap. Saying one frame is stiffer than another when the cranks, tires, wheels, pedals, shoes, air pressure, and terrain are different is completely flawed.
    "Big Gulps huh?...Allllriggghhht....Welp, See ya later!"

  9. #9
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    I guess you just have to follow the answer in all the threads and forums he started. He asked the same question in 3-4 forums 2 in 29er. Talk about wanting some answer.

  10. #10
    "Ride Lots" Eddy Merckx
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    Seriously...I hope he was able get that Dart 3 oil replaced after 10 hours of riding.
    "Big Gulps huh?...Allllriggghhht....Welp, See ya later!"

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