What is the official name of the bicycle gear gear?

I wonder what the official name of the bicycle gear gear is.

There are three stages in the front and eight stages in the back, so I don't know what the name of the cogwheel is called because it is bitten by the chain.

I think I need to replace or check this, what should I search for?

1200 2017-08-08 Gentleman

popular Do oats also have side effects?

A. 1

It's called a sprocket

Gentleman 7 years ago 0

A. 2

It's a sprocket
If you buy cheap ones from Alibal, they're a little over $11

Gentleman 7 years ago 0

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