Aravis said:
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I can't think of anything on a bike which would accurately be described as a cog. If there's no scope for confusion perhaps it doesn't matter very much?
Speaking of pedantry and all that. I can think of several things on a bike which can be described as cogs. Each sprocket has many cogs because a cog is one tooth on a sprocket or gear. A sprocket works with a chain. A gear is a wheel of cogs that meshes with other gears. Hence the English idiom of "I'm just a cog in the wheel here."
Link:
Here's a rhetoric question for you all: Should I not cringe when I read about steal bikes, peddling home and breaking to stop?