Transmission
Most modern motorcycles have a sequential manual transmission shifted by a foot lever. Some motorcycles, and many scooters, use a continuously variable transmission. Other types of automatic transmission and semi-automatic transmission are also in use.
Engine power can be engaged or interrupted through the clutch, typically an arrangement of plates stacked in alternating fashion, one geared on the inside to the engine and the next geared on the outside to the transmission input shaft.
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