I live by the beach. Although I guess this is a similar problem to those who ride on salt-laden winter roads...
It does take a while but, as evidenced by the endless bikes abandoned around the neighbourhood, eventually:
- the chain seizes (individual links seize and jam in the works), and/or
- the derailleur seizes (the spring stops pulling the mechanism left/right), and/or
- the cables seize (they do not move through the housing anymore), and/or
Actually, that's about it. Just those three things must be the root cause of 90% of the bikes abandoned in the neighbourhood; usually at, maximum, 5 years old. Sometimes, but rarely, the bottom bracket seizes, or the brakes jam, or the pedals jam, or the lock (if locked up) itself jams, but those three are the most commonly observed causes for end-of-life (at which point a malicious drunkard comes along and kicks the back wheel into a not-round-or-flat shape).
So, question, what can we do to mitigate these problems and keep them on the road a little longer?
Obviously, completely replacing those three parts every 3-4 years (plus the chainring), is a start but, advanced question, what materials can we replace them with to reduce the maintenance further.
Unfortunately, because the life-expectancy is so poor, and enthusiasm to be careless about locking it up so keen, price is a major concern. Is there such a thing as an all-plastic derailleur? Would the price of hydraulic lines really be worth the risk of theft? A hub and belt drive is perhaps ideal, but so expensive!
Just your two cents of insight please?