Page 1 of 2 1 2 LastLast
Results 1 to 25 of 33
  1. #1
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635

    saving a cracked frame??

    A few weeks ago, the frame cracked to my beloved 06 Haro V4.
    I had built up the Haro a few years ago 2007 V4.


    I took all the components off the Haro and built up an 06 S-Works Stumpjumper.


    After taking off all the components and getting ready to knock out the head tube racers, I got to looking at the frame.
    It was a 20" frame with a high seat tube.
    If I took off 3", there would be 5/8" of the seat tube above the weld at the top tube and seat stays.
    I would have to cut off the gusset and grind down the weld on the top tube and then cut the slot on the seat tube to allow the seat post clamp to tighten.

    I have nothing to loose if it doesn't work.

    Am I missing anything that would make this frame a hazard to ride or just a complete waste of time?
    If it works, the Cane Creek Thudbuster and spacer will not be used.

    Cracked seat tube








    This angle shows how much room I have to cut the slot on the seat tube for the seat tube clamp to work.
    Last edited by Dex; 02-25-2013 at 11:03 AM.
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  2. #2
    banned
    Reputation:
    Join Date
    Aug 2012
    Posts
    2,041
    Don't cut it ... Weld it, ream it, put a longer seat tube in it, hope for the best.

    Make sure you don't overheat the existing welds closest to the repair.

  3. #3
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Quote Originally Posted by bikeabuser View Post
    Don't cut it ... Weld it, ream it, put a longer seat tube in it, hope for the best.
    Thanks!
    Another benefit to cutting this frame down to a smaller size, is that my daughter's older Trek 4300 is to tall for her and 17" bike might be more in her size.

    3/12/13.... Disregard my comment there!
    Last edited by Dex; 03-13-2013 at 03:43 AM.
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  4. #4
    Picture Unrelated
    Reputation: zebrahum's Avatar
    Join Date
    Jun 2005
    Posts
    5,024
    Well, the gusset is there because the seat tube extends upward to increase standover while providing a stronger (in theory) solution to long seatposts. If you're not expecting to have much exposed seatpost then I would cautiously say to go for it; cut off the gusset and cut a new keyhole. Get a seatpost with plenty of insertion length that is the proper diameter.

    I don't see investing in welding and heat treating the frame to be a worthwhile investment when the crack is already propagating. Essentially the frame is a loss as-is so as long as you feel comfortable in your ability to keep an eye on your repair and assess when it needs to be binned then there's no reason you couldn't cut it. Just keep close watch on it and don't let a repair lull you into a false sense of accomplishment in frame repair.
    Don't you hate it when a sentence doesn't end the way you think it octopus?

  5. #5
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Quote Originally Posted by bikeabuser View Post
    Don't cut it ... Weld it, ream it, put a longer seat tube in it, hope for the best.
    Make sure you don't overheat the existing welds closest to the repair.
    bikeabuser
    when you say to "weld it" would that be like just running a bead over the crack?

    I think this is the reason for the crack.


    I think there was enough play below the shim to put pressure on the top of the seat tube. (just my opinion)

    An original size seat post of 30.6mm would be used in the repaired or shortened seat tube
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  6. #6
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Quote Originally Posted by zebrahum View Post
    Well, the gusset is there because the seat tube extends upward to increase standover while providing a stronger (in theory) solution to long seatposts. If you're not expecting to have much exposed seatpost then I would cautiously say to go for it; cut off the gusset and cut a new keyhole. Get a seatpost with plenty of insertion length that is the proper diameter.

    I don't see investing in welding and heat treating the frame to be a worthwhile investment when the crack is already propagating. Essentially the frame is a loss as-is so as long as you feel comfortable in your ability to keep an eye on your repair and assess when it needs to be binned then there's no reason you couldn't cut it. Just keep close watch on it and don't let a repair lull you into a false sense of accomplishment in frame repair.
    I see your points!
    The last thing I plan on doing is spending any money on it.
    This project gives me something to think about and work on after I get through building up this 07 IH Azure.
    07 IH Azure
    I'm getting to many irons in the fire LOL
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  7. #7
    mtbr member
    Reputation:
    Join Date
    Feb 2013
    Posts
    60
    Quote Originally Posted by Dex View Post
    bikeabuser
    when you say to "weld it" would that be like just running a bead over the crack?
    That's all I would do... if it was steel. Since your frame is aluminum, and aluminum has a memory and gets continuously weaker throughout it's lifetime, I'd say six years is a reasonable life for an aluminum frame ridden hard.

    I like your idea of cutting below the crack, and adding a notch for the clamping area. Although, if it's for your daughter, I wouldn't cheap-out and let her ride a frame that is past its useable life, because of the inherent danger. That frame is liable to kill someone, if you try to extend it's life too much. Be careful.

  8. #8
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Well it's now an 20" frame, with an 18" seat tube.
    Not sure what I'll do with it now.











    Last edited by Dex; 03-13-2013 at 03:46 AM. Reason: corrected my error in ststing that it is now a 18" FRAME
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  9. #9
    mtbr member
    Reputation:
    Join Date
    Feb 2013
    Posts
    60
    You did a really great job with that. It turned out really nice. Hope it works out for ya.

  10. #10
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Quote Originally Posted by Trilancing View Post
    You did a really great job with that. It turned out really nice. Hope it works out for ya.
    Thanks!
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  11. #11
    mtbr member
    Reputation: azorr's Avatar
    Join Date
    Jul 2012
    Posts
    296
    saving a cracked frame??-img_20130301_065037.jpgWow, thanks for this! I just had the exact same thing happen to my 2006 V4. I had already ordered the parts to build up a new 29er HT and am just waiting for them all to arrive, this bike was going to be passed to my wife to ride when we go on family rides. She would be just fine with an 18" frame, I am going to do this as well. I know mine broke because I didn't have enough seat post inserted into the frame. To be honest I have never thought about it and have ridden it like that since I bought it new in Oct. 2006. I am not worried about it breaking again on her as it won't likely leave pavement.

    Attachment 776473
    Last edited by azorr; 03-01-2013 at 11:50 AM.

  12. #12
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Whoa! That crack looks identical to mine.
    I used a thin blade hacksaw, a regular blade hacksaw and a file.
    Good luck!
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  13. #13
    sandbagger
    Reputation: airmiller44's Avatar
    Join Date
    Aug 2009
    Posts
    516
    you guys need to run your seatposts a lot further in lol. The frame isnt a hazard by cutting that down, and it doesnt mean the frame is weak and fatigued. it means someone put too much leverage and/or didnt have the post inserted enough. Cutting it was the best option
    V10.5 with Dorado pro and Vivid Air
    TWOSIXBIKES DJ prototype
    Www.twosixbikes.com
    www.facebook.com/twosixbikes

  14. #14
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Mine didn't crack due to running the seat post too high.
    I think mine cracked due to using a seat tube shim/spacer which probably equates to running a high seat tube.


    I ran with the Thud Buster seat post down so far, that half the CC logo on the post was not visible.
    Last edited by Dex; 03-07-2013 at 04:24 AM.
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  15. #15
    mtbr member
    Reputation:
    Join Date
    Mar 2013
    Posts
    7
    Sorry to hijack this thread, but I don't have enough posts to make my own thread. I cracked the chain stay on my cro-mo Gary Fisher. I have a MIG and a torch set. Would you MIG weld it or braze it?

  16. #16
    Picture Unrelated
    Reputation: zebrahum's Avatar
    Join Date
    Jun 2005
    Posts
    5,024
    Quote Originally Posted by joneill4 View Post
    Sorry to hijack this thread, but I don't have enough posts to make my own thread. I cracked the chain stay on my cro-mo Gary Fisher. I have a MIG and a torch set. Would you MIG weld it or braze it?
    Check out the FAQ's at the top of the builder's forum. I don't know much about MIG but I have read several times that it won't get you where you want to be. Brazing will likely be your best bet of the options.
    Don't you hate it when a sentence doesn't end the way you think it octopus?

  17. #17
    mtbr member
    Reputation:
    Join Date
    Mar 2013
    Posts
    7
    Thanks

  18. #18
    mtbr member
    Reputation:
    Join Date
    Mar 2013
    Posts
    7
    I know that I have seen the bike builders forum before, but for the life of me I can't find it.
    Nevermind I got it.
    Last edited by joneill4; 03-08-2013 at 04:52 AM. Reason: I'm an idiot

  19. #19
    mtbr member
    Reputation:
    Join Date
    Jul 2009
    Posts
    57
    Quote Originally Posted by Dex View Post
    Well it's now an 18" frame.
    Not sure what I'll do with it now.
    not to rain on your parade, but its not an 18" now...it just has a shorter seat tube. the top tube will still be way long for someone who needs an 18" frame.

  20. #20
    mtbr member
    Reputation: azorr's Avatar
    Join Date
    Jul 2012
    Posts
    296
    Here is my frame after receiving the same treatment:

    saving a cracked frame??-img_20130309_222722.jpgsaving a cracked frame??-img_20130309_222732.jpg

  21. #21
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Last edited by Dex; 03-13-2013 at 03:54 AM.
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  22. #22
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Quote Originally Posted by Metty View Post
    not to rain on your parade, but its not an 18" now...it just has a shorter seat tube. the top tube will still be way long for someone who needs an 18" frame.
    Metty, thanks for pointing that out to me!
    I edited that post and changed it to read
    "Well it's now an 20" frame, with an 18" seat tube."
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  23. #23
    Dex
    Dex is offline
    mtbr member
    Reputation: Dex's Avatar
    Join Date
    Sep 2004
    Posts
    635
    Quote Originally Posted by azorr View Post
    Here is my frame after receiving the same treatment:

    Click image for larger version. 

Name:	IMG_20130309_222722.jpg 
Views:	135 
Size:	226.5 KB 
ID:	779856Click image for larger version. 

Name:	IMG_20130309_222732.jpg 
Views:	115 
Size:	252.8 KB 
ID:	779857
    azorr
    great work! You did a much better job of removing the welds than I did.
    I'm about ready to build mine back.
    It will be interesting as to how screwed the dimensions will be going from a 20" to 18" seat tube.
    Noxubee Hills Trail System's FB page
    http://www.facebook.com/pages/Noxube...8499244?v=wall

  24. #24
    mtbr member
    Reputation: azorr's Avatar
    Join Date
    Jul 2012
    Posts
    296
    Thanks! I cheated on mine, you will notice in the background an angle grinder with a flap disc that made quick work of the welds. I am waiting on new cables and brake pads for mine, then I will clean up the stock parts and reassemble. Please let me know how your build goes.

    Quote Originally Posted by Dex View Post
    azorr
    great work! You did a much better job of removing the welds than I did.
    I'm about ready to build mine back.
    It will be interesting as to how screwed the dimensions will be going from a 20" to 18" seat tube.

  25. #25
    banned
    Reputation:
    Join Date
    Aug 2012
    Posts
    2,041
    Nice and clean, Guys ... I guess if one is looking to lower the seatpost, this is an obvious and practical solution.

    Did either of you completely remove the weld on the top tube ?
    If so, I hope that doesn't develop into another problem ... Keep us posted, if the tube fails at that location.

Page 1 of 2 1 2 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •