Well, a broken bike is a broken bike, I guess it happens, maybe the frame was invalid, who knows...
Nothing the warranty replacement frame cant fix :P
hopefully they are better then my chainstay replacement...what a fricken pain and costly too....another rider just gave a way his too...because you could buy a complete kona at wheelworld at a cheaper place then a replacement
the trick is ENJOYING YOUR LIFE EACH DAY, don't waste them away wishing for better days
Looks like the same area of the frame where all those intenses were breaking a couple years back.
You have a very rigid junction of tubes as the tt dt and ht are all welded together. There is stress on the tubes just before they all come together as they are more flexable than the joined tubes.
Not that it should break, but it is easy to see why it could break there.
does anyone have close up photos of the failure surface? it might be possible to tell what the failure mode was (i.e. shear failure versus tensile failure, for example).
in the pictures that uncle cliffy posted, it seems like something caused the material (i'm assuming some sort of aluminum alloy) to exceed its yield point, and move into plastic deformation. the pix that SMT posted showed failure w/o deformation. it's possible that it could be a combination of material defect (change in alloy microstructure due to welding) and also design defect (stress spiking beyond the yield point of aluminum in a load case not foreseen by the engineer)
does anyone have close up photos of the failure surface? it might be possible to tell what the failure mode was (i.e. shear failure versus tensile failure, for example).
in the pictures that uncle cliffy posted, it seems like something caused the material (i'm assuming some sort of aluminum alloy) to exceed its yield point, and move into plastic deformation. the pix that SMT posted showed failure w/o deformation. it's possible that it could be a combination of material defect (change in alloy microstructure due to welding) and also design defect (stress spiking beyond the yield point of aluminum in a load case not foreseen by the engineer)
Looks like the result of a large lateral force, like the forks slamming into the tubes in a big crash or frame hitting an object. If it was from the stresses of normal riding would you not expect the crack to be on the top or bottom.
Hopefully you will get a replacement, I am waiting on the outcome of my own warranty claim at the moment except mine is a coilair
Looks like the result of a large lateral force, like the forks slamming into the tubes in a big crash or frame hitting an object. If it was from the stresses of normal riding would you not expect the crack to be on the top or bottom.
Hopefully you will get a replacement, I am waiting on the outcome of my own warranty claim at the moment except mine is a coilair
Looks like the result of a large lateral force, like the forks slamming into the tubes in a big crash or frame hitting an object. If it was from the stresses of normal riding would you not expect the crack to be on the top or bottom.
Hopefully you will get a replacement, I am waiting on the outcome of my own warranty claim at the moment except mine is a coilair
From your picture, it looks like it broke where the gusset ends - if you inspect closely, there's likely an issue with the weld somewhere - cold, pinholes, or some other type of "stress riser". Also likely that it cracked first and you'll the rub marks to prove it.
Correct 2011 coilair, done a massive amount of riding on it in the last 4 months including mountain of hell and megavalanche, it has had 3 straight months of european bike parks and tracks.
I was at Leogang leading up to the world champs, first ride down the hill on the hangman 1 track all good. Second ride hit the first big patch of roots, large cracking sound lost the rear end all over the place went down hard in the roots. Thats basicly it, it has cracked straight through the lower edge of the weld, it could not be more on the weld seam. Hopefully kona will pick up the tab so to speak, as it was only purchased in Feb and only ridden from June to now.
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Originally Posted by Gemini2k05
