Originally Posted by
spectastic
now to address the cons..
- can p clamps provide enough support for a 30-40 lb loaded rack? furthermore, can a typical well built carbon seat stay handle the extra weight at the lower seat stay joints? (the answer varies with the build, so let's just make a sensible assumption that the frame is more a cx frame, and not a tarmac, cervelo, cannondale evo, or any of the race style bikes)
- how common are frame damage in a given tour? where are the failures most common? (if it's bb, head tube, or dropouts, it's probably game over)
- carbon fiber frames can be protected. people have used inner tubes, or other polymeric material that disperses the force. are these generally adequate to protect the carbon frame for a long tour?
- I'm sure there are ways to make a carbon bike look ugly (eg. wrap it in inner tube)
- I get it, Murphy's Law.. carbon fiber isn't designed to handle forces equally in all directions. but again, assume that it's a well built cx frame, not a superlight giant propel advanced sl... what are some specific touring scenarios where a carbon fiber frame would be at risk?
My ideal touring bike would probably be carbon fiber, but I doubt that I would choose it for the usage you propose. I would think of ways to reduce your proposed gear weight long before even considering a CF bike unless maybe you will be pulling a trailer.
- P clamps on carbon are probably a bad idea. There are other answers including using the brake bridge bolt and skewers. Also canti brake bosses work if you have them. Then there are the various rackless solutions.
- Probably not a problem until you start carrying too much and/or start using p clamps. BTW, repairs can be done with epoxy and cloth so doing a roadside repair may actually be easier than with a metal frame. I think the notion of repairing frames on tour is kind of a stretch any way, since for short tours the tour is probably over and for a long one getting another whole bike or a frame sent from home may be a more likely option.
- I wouldn't bother. Just use reasonable care. Their fragility is often overstated.
- Again I wouldn't bother. Use reasonable care in where you leave the bike and don't worry. If you really must put a few splotches of primer here and there.
- I really don't think the risk is any big deal. You do want to avoid sharp stress points like p clamps. You also want to take some care to minimize impacts with sharp objects.
The big question is why would you bother to go carbon and then carry 30-40 pounds of stuff? It is pretty easy to camp and cook with 20 pounds of gear. It seems like you would start by leaving a lot of that 30-40 pounds of stuff home before going to CF for the frame.