Difference between two stroke engine and four stroke bike engine?

The main differences between a two-stroke engine and a four-stroke engine, commonly found in bikes, lie in their design, operation, and efficiency:
Cycle:
Two-stroke engine: Completes the intake, compression, power, and exhaust strokes in just two movements of the piston (one upstroke and one downstroke).
Four-stroke engine: Completes these four strokes in four separate movements of the piston.
Lubrication:
Two-stroke engine: Typically requires oil to be mixed with the fuel for lubrication, as there is no separate lubrication system.
Four-stroke engine: Has a separate oil lubrication system, where oil is stored in a crankcase and circulated through the engine to lubricate moving parts.
Efficiency:
Two-stroke engine: Tends to be less fuel-efficient and more polluting due to its simpler design and the mixing of oil with fuel.
Four-stroke engine: Generally more fuel-efficient and produces fewer emissions because it has a more controlled combustion process and separate lubrication system.
Power Delivery:
Two-stroke engine: Provides power with every revolution of the crankshaft, resulting in a smoother power delivery but less torque compared to a four-stroke engine.
Four-stroke engine: Delivers power once every two revolutions of the crankshaft, resulting in a more consistent torque delivery throughout the RPM range.
Maintenance:
Two-stroke engine: Typically requires more frequent maintenance due to its simpler design and higher operating speeds.
Four-stroke engine: Generally requires less frequent maintenance intervals due to its more complex design and lower operating speeds.
Overall, while two-stroke engines are simpler and lighter, they tend to be less fuel-efficient and more polluting compared to four-stroke engines, which offer better fuel economy, lower emissions, and smoother power delivery.