Exploring motorcycle engines – types and working principles unveiled
As the core component of the motorcycle, the motorcycle engines are not only loved by riders with diverse design and powerful performance, but also provide power through the solid mechanical structure, adding unlimited fun to the ride.
The article will give a deeper understanding of the principles and classifications of motorcycle engines so as to better understand their important role in the world of cycling.
You can also check the other articles in our website to know more information about motorcycle components and replacement including:
The motorcycle engine consists of the body, crank connection rod mechanism, gas distribution mechanism and fuel supply system, intake and exhaust system, cooling system, lubrication system and ignition system.
Motorcycle engines components and their functions
Airframe Composition: Composed of crankcase, cylinder head and cylinder block. Function: Support and install other components to withstand various impact forces and torques generated during engine operation.
Crank linkage mechanism Composition: piston, piston ring, piston pin, connecting rod, connecting rod size head bearing, crankshaft, etc.
Function: The linear reciprocating motion of the piston becomes the rotating motion of the crankshaft, thus outputting power and driving the accessories to work.
Valve mechanism Composition: camshaft, valve, valve seat, valve spring, valve guide, rocker arm, rocker arm shaft, etc. Function: Timely inhalation of combustible mixer and timely exhaust gas in cylinder.
Fuel supply system Composition: fuel tank, fuel switch, carburetor, etc. Function: According to the working condition of the engine, supply sufficient proportion of the appropriate combustible mixture.
Intake and exhaust system
Composition: The intake system consists of an intake pipe, air filter, intake valve, etc. Function: The intake system guides and filters air to control the volume of mixed gas entering the cylinder. And the exhaust system is designed to discharge exhaust gas and reduce exhaust noise.
Cooling system Composition: water pump, thermostat, water seal, cooling channel, radiator, cooling fan, etc. Function: Cool the engine to ensure the normal operation of the engine.
Lubrication system Composition: Composed of oil pump, filter screen, oil passage and fine filter. Function: Provide sufficient lubricating oil for moving parts to reduce wear of the parts.
Ignition system Composition: Composed of magneto, CDI, ignition coil, cable, spark plug.
Function: Timed ignition of the mixture in the combustion chamber.
Classification of motorcycle engines
The motorcycle engines are available as two – and four-stroke engines.
Two-stroke engine where the engine crankshaft rotates once, that is, the piston moves two strokes down and down to complete a working cycle of the engine.
Four-stroke engine where the engine crankshaft rotates twice, that is, the piston moves up and down four strokes to complete a working cycle of the engine.
Working cycle: refers to the working process of the motorcycle engines composed of intake air, compression, combustion expansion (work) and exhaust stroke. The process of the engine completing an intake, compression, work and exhaust is called a working cycle, also known as a cycle.
Structure, working principle and advantages and disadvantages of a two-stroke engine
Structures of a two-stroke engine The two-stroke engine is also composed of main components such as cylinder block, crankshaft, piston and connecting rod, but it does not have complex intake and exhaust valve assemblies and CAM valve mechanisms. Gas exchange is achieved through small holes in the cylinder wall called air inlets and exhaust ports, which are used to draw in air and expel exhaust gases. The piston also opens and closes these ports as it moves up and down.
Working principle a two-stroke engine The working process of a two-stroke engine is also divided into four stages: intake, compression, work and exhaust, but they are all concentrated in two strokes. The key lies in the design of the engine, which allows a mixture of air and fuel to be admitted and compressed simultaneously. Because in the intake stage, the mixture of air and fuel is first stored in the crankcase, waiting for the air intake to be opened with the movement of the piston before entering the cylinder.
Advantages of a two-stroke engine The biggest advantage of a two-stroke engine is that its output power is significantly higher than that of a four-stroke engine with the same displacement. This is because it does work once every turn (two strokes), while a four-stroke engine needs two turns to do work once.
In addition, because there is no complex CAM valve mechanism, the structure of the two-stroke engine is very simple, which reduces the weight of the engine, manufacturing costs, and failure rate.
Disadvantages of a two-stroke engine The time of each working part of a two-stroke engine is shorter, so the mixing effect of fuel and air is not as full as that of a four-stroke engine, the combustion process is not as full as that of a four-stroke engine, and the fuel consumption is higher.
In addition, because the two-stroke engine wear more serious, which also makes its service life is much lower than the four-stroke engine.
The working principle, advantages and disadvantages of a four-stroke engine
Working principle of a four-stroke engine Intake stroke During the intake stroke, the crankshaft drives the piston from top dead center to bottom. The intake valve opens and the mixture of gasoline and air is drawn into the cylinder. When the piston reaches the bottom dead center, the intake stroke ends.Compression stroke At the end of the intake stroke, the piston has reached the bottom dead center, and the cylinder has been filled with a mixture of gasoline and air. The crankshaft continues to drive the piston from the bottom dead center to the top dead center, the intake and exhaust valves are closed, the mixture is compressed, and the pressure and temperature are increased until the piston reaches the top dead center and the compression stroke ends.
Expansion stroke The compression stroke is about to end, before the piston reaches the top dead center at some point, the high voltage provided by the ignition system acts on the spark plug, the spark plug jumps fire, igniting the mixture of the cylinder, the mixture begins to burn rapidly and expand to do work, push the piston down, drive the crankshaft output power, reach the bottom dead center, and the work stroke ends.
Exhaust stroke After the end of the work stroke, the piston reaches the bottom dead center, and the crankshaft drives the piston from the bottom dead center to the top dead center. At this time, the exhaust valve should be opened, and the exhaust gas after combustion is discharged through the exhaust valve. The exhaust stops, the piston is at TDC, and the next intake stroke begins.
Advantages of a four-stroke engine
Optimum air intake, compression, expansion (explosion), exhaust each process is carried out separately, so the work is reliable, high efficiency and good stability. The speed range from low speed to high speed is large (more than 500 to 1000rpm).
The fuel consumption of the four-stroke engine is low, and there is no gas channeling return loss like that of the two-stroke engine.
Low speed smooth operation, rely on lubrication system lubrication, not easy to overheat.
Long intake process and compression process, high volumetric efficiency and average effective pressure.
Less heat load than a two-stroke engine. Do not worry about deformation, ablation problems. Large displacement can be designed to be high power
Disadvantages of a four-stroke engine
Valve mechanism is complex, many parts, difficult to maintain
The machinery is noisy
Because the crankshaft bursts twice, the rotational balance is unstable.
Conclusion
Through the panoramic survey of the motorcycle industry market in Thailand and the analysis of power replacement solutions, this paper finds that the market is developing rapidly. The popularity of electric motorcycles and the application of power replacement technology have brought great potential and business opportunities to the industry.
Battery swapping solutions improve ease of use, solve battery life and charging time problems, and promote technological progress and market expansion.
In the future, Thailand’s motorcycle industry will develop towards intelligence and environmental protection. Through joint efforts, Thailand is expected to become a leading market for electric motorcycles and power-changing technologies in Asia, contributing to the global green transportation cause.
Tess
Hi! I am a senior writer in the two-three-wheeler battery swapping industry, with many years of writing experience, committed to providing the ultimate knowledge, services and a complete set of battery swapping solutions for various industries.
Exploring motorcycle engines – types and working principles unveiled
As the core component of the motorcycle, the motorcycle engines are not only loved by riders with diverse design and powerful performance, but also provide power through the solid mechanical structure, adding unlimited fun to the ride.
The article will give a deeper understanding of the principles and classifications of motorcycle engines so as to better understand their important role in the world of cycling.
You can also check the other articles in our website to know more information about motorcycle components and replacement including:
Motorcycle battery trickle charger
Motorcycle controller
Electric motorcycle hub motor vs mid drive
Electric motorcycle drivetrain
Electric motorcycle frame
Motorcycle brake
Motorcycle handlebar
Motorcycle battery replacement
Structures of motorcycle engine
The motorcycle engine consists of the body, crank connection rod mechanism, gas distribution mechanism and fuel supply system, intake and exhaust system, cooling system, lubrication system and ignition system.
Motorcycle engines components and their functions
Airframe
Composition: Composed of crankcase, cylinder head and cylinder block.
Function: Support and install other components to withstand various impact forces and torques generated during engine operation.
Crank linkage mechanism
Composition: piston, piston ring, piston pin, connecting rod, connecting rod size head bearing, crankshaft, etc.
Function: The linear reciprocating motion of the piston becomes the rotating motion of the crankshaft, thus outputting power and driving the accessories to work.
Valve mechanism
Composition: camshaft, valve, valve seat, valve spring, valve guide, rocker arm, rocker arm shaft, etc.
Function: Timely inhalation of combustible mixer and timely exhaust gas in cylinder.
Fuel supply system
Composition: fuel tank, fuel switch, carburetor, etc.
Function: According to the working condition of the engine, supply sufficient proportion of the appropriate combustible mixture.
Intake and exhaust system
Composition: The intake system consists of an intake pipe, air filter, intake valve, etc.
Function: The intake system guides and filters air to control the volume of mixed gas entering the cylinder. And the exhaust system is designed to discharge exhaust gas and reduce exhaust noise.
Cooling system
Composition: water pump, thermostat, water seal, cooling channel, radiator, cooling fan, etc.
Function: Cool the engine to ensure the normal operation of the engine.
Lubrication system
Composition: Composed of oil pump, filter screen, oil passage and fine filter.
Function: Provide sufficient lubricating oil for moving parts to reduce wear of the parts.
Ignition system
Composition: Composed of magneto, CDI, ignition coil, cable, spark plug.
Function: Timed ignition of the mixture in the combustion chamber.
Classification of motorcycle engines
The motorcycle engines are available as two – and four-stroke engines.
Two-stroke engine
where the engine crankshaft rotates once, that is, the piston moves two strokes down and down to complete a working cycle of the engine.
Four-stroke engine
where the engine crankshaft rotates twice, that is, the piston moves up and down four strokes to complete a working cycle of the engine.
Working cycle: refers to the working process of the motorcycle engines composed of intake air, compression, combustion expansion (work) and exhaust stroke. The process of the engine completing an intake, compression, work and exhaust is called a working cycle, also known as a cycle.
Structure, working principle and advantages and disadvantages of a two-stroke engine
Structures of a two-stroke engine
The two-stroke engine is also composed of main components such as cylinder block, crankshaft, piston and connecting rod, but it does not have complex intake and exhaust valve assemblies and CAM valve mechanisms. Gas exchange is achieved through small holes in the cylinder wall called air inlets and exhaust ports, which are used to draw in air and expel exhaust gases. The piston also opens and closes these ports as it moves up and down.
Working principle a two-stroke engine
The working process of a two-stroke engine is also divided into four stages: intake, compression, work and exhaust, but they are all concentrated in two strokes. The key lies in the design of the engine, which allows a mixture of air and fuel to be admitted and compressed simultaneously. Because in the intake stage, the mixture of air and fuel is first stored in the crankcase, waiting for the air intake to be opened with the movement of the piston before entering the cylinder.
Advantages of a two-stroke engine
The biggest advantage of a two-stroke engine is that its output power is significantly higher than that of a four-stroke engine with the same displacement. This is because it does work once every turn (two strokes), while a four-stroke engine needs two turns to do work once.
In addition, because there is no complex CAM valve mechanism, the structure of the two-stroke engine is very simple, which reduces the weight of the engine, manufacturing costs, and failure rate.
Disadvantages of a two-stroke engine
The time of each working part of a two-stroke engine is shorter, so the mixing effect of fuel and air is not as full as that of a four-stroke engine, the combustion process is not as full as that of a four-stroke engine, and the fuel consumption is higher.
In addition, because the two-stroke engine wear more serious, which also makes its service life is much lower than the four-stroke engine.
The working principle, advantages and disadvantages of a four-stroke engine
Working principle of a four-stroke engine
Compression stroke
Intake stroke
During the intake stroke, the crankshaft drives the piston from top dead center to bottom. The intake valve opens and the mixture of gasoline and air is drawn into the cylinder. When the piston reaches the bottom dead center, the intake stroke ends.
At the end of the intake stroke, the piston has reached the bottom dead center, and the cylinder has been filled with a mixture of gasoline and air. The crankshaft continues to drive the piston from the bottom dead center to the top dead center, the intake and exhaust valves are closed, the mixture is compressed, and the pressure and temperature are increased until the piston reaches the top dead center and the compression stroke ends.
Expansion stroke
The compression stroke is about to end, before the piston reaches the top dead center at some point, the high voltage provided by the ignition system acts on the spark plug, the spark plug jumps fire, igniting the mixture of the cylinder, the mixture begins to burn rapidly and expand to do work, push the piston down, drive the crankshaft output power, reach the bottom dead center, and the work stroke ends.
Exhaust stroke
After the end of the work stroke, the piston reaches the bottom dead center, and the crankshaft drives the piston from the bottom dead center to the top dead center. At this time, the exhaust valve should be opened, and the exhaust gas after combustion is discharged through the exhaust valve. The exhaust stops, the piston is at TDC, and the next intake stroke begins.
Advantages of a four-stroke engine
Disadvantages of a four-stroke engine
Conclusion
Through the panoramic survey of the motorcycle industry market in Thailand and the analysis of power replacement solutions, this paper finds that the market is developing rapidly. The popularity of electric motorcycles and the application of power replacement technology have brought great potential and business opportunities to the industry.
Battery swapping solutions improve ease of use, solve battery life and charging time problems, and promote technological progress and market expansion.
In the future, Thailand’s motorcycle industry will develop towards intelligence and environmental protection. Through joint efforts, Thailand is expected to become a leading market for electric motorcycles and power-changing technologies in Asia, contributing to the global green transportation cause.