Originally Posted by
lightspree
Titanium is extremely corrosion resistant.
There are coatings made to protect the insides of steel bike tubing. There are waxes and other coatings that help protect the outsides. Still though, ti and stainless are better.
Between the two, ti and stainless, ti is more corrosion resistant. Stainless steels vary quite a bit. Some stainless steels are formulated (alloyed) to be more corrosion resistant. They are used in marine environments, and in better watches and jewelry that will hold up under heavy exposure to sweat and body oils and acids.
I don't know where 953 is on the stainless steel corrosion resistance spectrum. I've heard it is good, but if you ride on salt roads a lot, it could be a problem, and you would want extra protection (protective coatings, and care such as preventive rinsings, or using a beater when conditions are bad).
I'm reminded of NYC Bike Snob's image of his stainless steel Ritte:
I personally have never had an issue with corrosion on steel bikes. Admittedly, due to moving countries and the like, the oldest one I own is only 17 years old, but the only rust on that is on the bottle cage bolts, and it got left outside in the rain on many occasions as a commuter. Using a steel bike as a "nice" bike (i.e. one you love rather than beat up), I would not be concerned about corrosion personally, although I understand that my anecdotal evidence is worth about as much as anyone elses.