this post was submitted on 03 Jun 2025
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God damnit, that was an expensive ride.

Now I’m trying to find one identical to this so I can use it for parts. I just hope this isn’t a common issue with this frame and that I just got unlucky with mine.

Would’ve been an easy fix if the frame were steel - but from what I understand, welding isn’t really an option with these alloy frames.

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[–] [email protected] 11 points 6 days ago (2 children)

Holy. Ballz. Between you and @[email protected], this is starting to resemble a generalized design flaw. DerPlouk's break looks like more like a stress riser, whereas yours looks like an HAZ. Aaaannd that is the about the outer limit of my metal failure analysis skills.

Are there any welders or metallurgists in the house? I would love to read a failure analysis of how and why this happened right at that spot.

[–] [email protected] 12 points 6 days ago (1 children)

Strain-stress for aluminum had a finite lifetime limit, so after X stress over the life of the part it will break, where steel is almost infinite as long as it's below the per instance maximum

[–] [email protected] 4 points 6 days ago

Someone aluminums!

[–] [email protected] 6 points 6 days ago* (last edited 6 days ago)

I mentioned this to chatGPT earlier, and it correctly guessed the exact location where the frame cracked, so I assume it’s simply a high-stress zone. Makes sense though - when I’m sitting down and bouncing over heavy rocks and roots, that’s the part of the frame that takes the brunt of the force, preventing the rear triangle from folding in.

I’m not the smallest guy, and I usually have a heavy backpack on, which surely doesn’t help either. That being said - the frame is rated for 120 kg, and I stay well below that, so it's most likely a manufacturing defect.