OK, stuff breaks. I’ve seen pictures of Marin Titanium frames that have had the seat tube shear off at the bottom bracket – and even made in the good ol’ USA Lyndsky/On-One frames where the dropouts have broken away.
Sooo, it stands to reason someone’s going to break an XACD frame too. As part of the ongoing research on buying my frame I found two references to frames breaking. One was a dropout crack on a 2004 29’er over on the MTBR forum:
Looks like this could be a common area to fail as another rider mentions exactly the same problem with a Setavento frame which were also made by XACD again over on the MTBR forum.
Looking at where this has cracked I’d say it’s because of the extra crimping around the end of the tube rather than a welding failure.
Another involved someone who’d had the chainstays crack where they’d been squashed super thin – I’m not surprised given how over manipulated this area can be on XACD frames. It’s the reason I specified a lesser clearance on ‘Love You Long Time’. You can see similar super crimping on other XACD frames like those made for Carver bikes, 29’ers might be more susceptible to this as the chainstay has to come in at a tighter angle around the wheel.
The other biggie I found when looking for XACD failures were references to a fork they made for a company called Spicer. From the fail picture it looks like these broke because the tubing was too thin/not large enough diameter rather than because a weld was weak.
As someone else commented, XACD are a builder not a designer and while they will offer advice if they think something you’re doing might not work, ultimately they just build what you ask them to.