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  1. #1
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    XCL Seatpost clamp size

    What is the seatpost clamp size for a XCL?

    Thanks in advance.

  2. #2
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    response

    Quote Originally Posted by JTBAZ
    What is the seatpost clamp size for a XCL?

    Thanks in advance.
    38.5 I have them in stock.

    A.
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  3. #3
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    Quote Originally Posted by CHUMBAevo
    38.5 I have them in stock.

    A.
    You mean 38.1mm.

  4. #4
    RJG
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    I recently purchased an 08 XCL and the frame came with a QR Chumba clamp. Does Chumba or anyone make a bolt on clamp in the correct size?
    R

  5. #5
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    Yeah - try DKG. They make a bolt on clamp in 38.1mm.

  6. #6
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    Quote Originally Posted by RJG
    I recently purchased an 08 XCL and the frame came with a QR Chumba clamp. Does Chumba or anyone make a bolt on clamp in the correct size?
    R
    Call Chumba - I ordered a bolt on clamp directly from Chumba.'

    Jeff

  7. #7
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    So which is it, 38.1 or 38.5? I cant find a 38.1 anywhere. I am tired of my post slipping!

  8. #8
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    It is 38.5. The largest size Hope makes. You can order one from them - we stock them also - or order a CHUMBA clamp from us. http://www.hopetechusa.com/voir_SCN.html
    Last edited by CHUMBAevo; 04-25-2009 at 10:38 AM.
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  9. #9
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    Quote Originally Posted by CHUMBAevo
    It is 38.5. The largest size Hope makes. You can order one from them - we stock them also - or order a CHUMBA clamp from us. http://www.hopetechusa.com/voir_SCN.html
    I dig the Chumba clamps, But is there a new design or something? If it is the same design would'nt it just continue to slip? How much are the Chumba ones? I was thinking about calling you guys to buy a jersey, i could pick one of these up at the same time, but i want to make sure it will keep my post from slipping.

  10. #10
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    From what the others have said you may need to call them as questions here on the forum are not really the right forum or something.
    Frankenstein doesn't scare me ...

  11. #11
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    ..

    Quote Originally Posted by Daddy_ja
    I dig the Chumba clamps, But is there a new design or something? If it is the same design would'nt it just continue to slip? How much are the Chumba ones? I was thinking about calling you guys to buy a jersey, i could pick one of these up at the same time, but i want to make sure it will keep my post from slipping.
    We do have newly designed ones - the one with the compass design - the other one shouldn't slip - how is it slipping - is the allen bolt coming loose?
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  12. #12
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    No matter how hard you clamp it down, the seat post will still rotate when you put pressure on the side of the seat. Like its not gripping the post well enough.

  13. #13
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    Quote Originally Posted by Daddy_ja
    No matter how hard you clamp it down, the seat post will still rotate when you put pressure on the side of the seat. Like its not gripping the post well enough.
    I have the old design Chumba quick release and a Thomson seat post and it doesn't move at all. Did you grease your seat post when you installed it (maybe have to much on)? Also, how do you have your seat clamp on your bike? Do you have the slot on the clamp lined up with the slot on the seat tube?

  14. #14
    I'm living the dream!
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    What kind of post do you have? If possible borrow another post and see if it slips. On a previous bike, I had that happen with a Thomson post and no matter how much I torqued down the clamp (Salsa), the post wouldn't stay put. I put in an old Race Face post I had and there was no slipping at all. I contacted Thomson and did a swap via mail and the new post had zero slip. I guess it was just a bad one.

  15. #15
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    Quote Originally Posted by Daddy_ja
    No matter how hard you clamp it down, the seat post will still rotate when you put pressure on the side of the seat. Like its not gripping the post well enough.
    Triple check the size of your post and clamp.
    Do the clamp ends have a gap when clamped or are they touching?
    I think I have the newer style and I'm 230 lbs and on the couple of short street rides I've been on the seat, post and clamp all feel stout.
    pic is of mine currently.

    Edit: is it possible to dent a post all the way around by clamping it too hard? try moving the post further up or down and retry the clamp maybe?
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    Frankenstein doesn't scare me ...

  16. #16
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    Quote Originally Posted by Thor821
    I have the old design Chumba quick release and a Thomson seat post and it doesn't move at all. Did you grease your seat post when you installed it (maybe have to much on)? Also, how do you have your seat clamp on your bike? Do you have the slot on the clamp lined up with the slot on the seat tube?
    No grease on the post (Thomson). Slot is to the back. Clamp and post are the correct size. Yes there is still a gap when i clamp it down. The Clamp wont let me clamp after i get to a certain point, example... i can clamp it with bolt at position A, but if i tighten the bolt 1/4 of a turn more, the clamp will no longer close no matter how hard you try. I would say that it is just at the point where the slot side are touching and that is why it wont clamp any further, but this is not the case. It just seems like it doesnt want to clamp down all the way. I can make it tight by closing the clamp and then tightening the bolt, but the problem is i adjust the post up and down on my rides, so i dont want to be having to use an allen key every time i adjust it.

  17. #17
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    10-4.
    Maybe post a few pics of the clamp and what it is or isn't doing. Maybe that can help shed some light. Got me stumped man.
    Frankenstein doesn't scare me ...

  18. #18
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    Is your clamp like any of these?

    http://www.thefind.com/sports/info-alloy-seatpost-clamp

    Does your clamp have a small plastic washer/plate between the lever end and the clamp?
    Could it be missing? Or is the fulcrum(okay, okay pivot washer any better?) built into the clamp like on mine above?
    Last edited by ecrock45; 04-26-2009 at 05:07 PM.
    Frankenstein doesn't scare me ...

  19. #19
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    ok, so i came home on my lunch break to look at it again. There is no spacer between the lever and the clamp, but i think i found the major problem... I took the bolt all the way out and the barrel nut out of the lever and low and behold there are some nasty gouges out of the inside of the lever where the bolt catches if tightened to far. So it looks to me like the bolt is just a tad to long and that is what is keeping me from being able to clamp down as hard as needed. So has anyone else had this problem with the older Chumba clamp, or am i the unique one? Looks like i just need to trim 1/8 of an inch or so off of the bolt and it should be good to go! I will try and post pics later this evening when i have more time. So what do you guys think?

    Thanks,
    Jason

  20. #20
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    So i went ahead and lopped off about 1/8" and waddya know, no more clamping issues! The clamp tightens down great on the post and the seat no longer moves! For any others out there that may still be having clamping issues, check out those bolt lengths and make sure it is not binding on the lever. Thanks for the help fellas! now i just need to post up some pics of my build, since i am new to the CHUMBA family.

    Jason

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