TRANSMISSION GEAR SET
Engine parts is an engine that powers a motorcycle.
Motorcycle engines are typically two-stroke or four-stroke internal combustion engines, but other engine types (such as Wankels and electric motors) have been used in small numbers. Although some mopeds had friction drive to the front tyre, a motorcycle engine invariably drives the rear wheel, power being sent to the driven wheel by belt, chain or shaft. Most engines have a gearbox with up to six ratios. Reverse gear is occasionally found on heavy tourers and sidecar motorcycles.Gear changes are normally effected using a foot-pedal and manual clutch, but early models had hand-levers. Some bikes have automatic or semi-automatic gearboxes.
Motorcycle often have the engine as part of the rear suspension, so the engine is not fixed rigidly to the main frame. Instead, the combined engine-transmission-swingarm assembly is pivoted to follow the road surface and is part of the “unsprung weight”. The chain final-drive of scooters runs in an oil-bath within the engine casings. “Step-through” motorcycles may have a rigidly fixed engine, or may have a scooter-type arrangement.