How long does an aluminium frame lasts in a touring bike?
[Removed extra questions to be clear.]
Background
So far I preferred aluminium vs. steel for many reasons, but if steel lasts significantly longer, for my next touring bike I will go for steel.
My Cannondale Badboy 2004 has a crack in the alu-frame. I was surprised by this, I thought my bike will last 20+ years easily. The workshop they said this is a high quality, strong frame, but after 10 years alu frames can get tired. Especially if I use my bike both in winter and summer, as the heat change wear alu faster. They say it can be welded, which will cost significantly less vs. a new frame (if it is available), but I should be prepared for other cracks to appear. The workshop contracts a welder specialized in bike frame welding and repair.
I also found a scientific research article on this topic. If someone has access to ScienceDirect (Cicero et al. (2011): *Analysis of the cracking causes in an aluminium alloy bike frame*), I'd be interested in the conclusions.
I'm interested in touring bikes, not road bikes, city bikes, etc.
I'm happy to update/clarify my question if needed, make a comment.
Topics I have researched:
- Maintenance on an Aluminium frame
- Which type of frame is better for a touring bike, steel or aluminium?
- Is it possible to repair a dent on an aluminium frame?
- What are the pros and cons between an aluminium and carbon frame?
- Is torque relevant for steel/aluminium? Where do I find torque specs?
- non-steel frames and longevity
- http://forums.mtbr.com/frame-building/aluminum-welding-cracked-frame-134600.html
- http://singletrackworld.com/forum/topic/repairing-a-cracked-frame
Crack in the alu frame near the rear axe (the bike is upside down):
