Some of us that live in northern USA are often exposed to de-icing chemicals applied to roads here in winter, especially after a snow or ice event. Salt is used, some forms of the salt are sea salt, or mined from salt deposits. And in some places, salt is added on sidewalks for walking too. Thus, riding anywhere near this, and salty water gets on anything on your bike. There will be puddles of salty water everywhere.

The first time I rode one of my bikes in winter, I was surprised how even the aluminum crankset was heavily oxidized, that I did not expect. You only have to ride through a few puddles of salty water to get your bike coated with very corrosive salt water.

One of my neighbors is a bike mechanic at a large bike shop on a large University campus where there are a lot of bikes, most are just stored outside in winter, but some are ridden through winter. He was telling me that they replace a lot of chains every spring. Instead of removing old chains like most of us do with a chain tool to drive out a pin or disconnect a quick link, they often use a heavy duty bolt cutter to save time. And if heavily corroded, pressing out a pin or disconnecting a quick link can be difficult too. Since the chain is going into the recycle bin, does not matter if the chain is ruined when removed.

I assumed they use deicing chemicals on roads in Finland, perhaps I was wrong about that.

I just pasted this from the current forecast for where I live:



Not only do they plow the snow off the roads, but the apply de-icing chemicals, mostly salt, to cut the ice that accumulates. And it gets everywhere.