BroDeal said:
Carbon and ti frames are not built to the same weight, so that it irrelevant.
I disagree. If you're trying to say "you can't compare CF and Ti bikes because they're fundamentally different critters" that's fine, but you can't allow the comparison and cherry-pick the advantages of one material but ignore the advantages of another. Much of the claimed superiority of metals including Ti is due to their inferior mechanical properties (tensile strength WRT CF) in terms of meeting design-specific stresses. Essentially, to be strong enough to deal with the forces of normal riding, a frame built with a traditional drawn metal tubeset, whether Al, Ti or Fe, ends up 'overbuilt' (again WRT CF) in terms of resistance to damage. You could just as easily build some extra strength for crash worthiness into CF; this happens with MTBs).
Witness what happens to lightweight alloy bikes, or steel bikes built with modern ultra-thin tube sets; neither crash worthy nor repairable. Perhaps this hasn't happened yet with Ti because such tubesets are too hard to draw in Ti, but it's still not "irrelevant" if the OP is
comparing two bikes made from the different materials, ostensibly for the same
use.
BroDeal said:
You have never seen any carbon MTBs with a cracked swing arm, or carbon bars and seatposts that have broken in a crash (or in some cases failed unexpectedly)?
Actually, I haven't, but that's probably because CF MTBs are still in the minority; I don't doubt they are similarly susceptible to breakage. I have seen broken alloy swingarms, broken alloy frames, broken alloy bars, broken alloy forks and broken alloy cranks, broken arms, broken collarbones and broken balls however
My own opinion is that if you have a crash that results in visible damage to your bike,
whatever material it's made from, you would be a fool to ride it faster than walking pace until you're able to get it professionally examined AND tested. On the flip side, I see no justification for the paranoia about 'invisible' crash damage to CF; any deformation significant enough to affect the CF material would almost certainly result in visible, tangible damage to the clearcoat.
Of course, if you know of any evidence to the contrary I wold love to read it as it might one day save my life!