What is the crank?

Crank on a bicycle: 2 radially and oppositely arranged arms, connected to a shaft, which run through the bottom bracket.

Crank:
2 radially and oppositely arranged arms, connected to a shaft that runs through the bottom bracket. The crank system converts the pedaling movement of the legs into a rotational movement of the crank. The pedals are screwed onto the outer part of the crank arms.

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