Table of Contents

How does a motorcycle internal combustion engine work?

A motorcycle engine works by converting the energy from an explosive fuel-air mixture into mechanical energy, which is then used to power the motorcycle:

1. Fuel-air mixture

The engine takes in a fuel-air mixture through valves and into the combustion chamber.
2. Compression

The piston moves down, compressing the fuel-air mixture.
3. Ignition

A spark plug ignites the compressed fuel-air mixture, causing it to burn and release heat.
4. Expansion

The burned gases expand, creating high pressure that drives the piston back down, spinning the crankshaft.
5. Exhaust

The exhaust valve opens, allowing the burned gases to escape the cylinder. The piston rises, helping to push the remaining gases out.
6. Repeat

The cycle repeats. This sequence of events is called the four-stroke cycle.

The crankshaft is connected to a flywheel, which helps keep the engine rotating smoothly. The crankshaft’s rotational force is then transmitted through the transmission to the rear wheel of the motorcycle.

The transmission system includes the clutch, gear-box, and final-drive chain. The clutch allows the rider to engage and disengage the engine from the wheels. The gear-box allows the rider to select the amount of power they need from the engine.

four-stroke cycle piston makes two up strokes and two down strokes per cycle

inake Piston down air/fuel mixture by valves controlled by camshaft. (piston down) (fuel injector or carburetor)
Compressions (piston up)
spark (piston down)
exhaust volves open to out he gases (piston up)

When piston up compress the air/fuel mixture spark plug sparks and ignite the mixture and push piston down.

Piston have piston rings just like needle syrangee’s plunger

compression ring is to seal the gap between the piston and the cylinder walls. ensure that the air-fuel mixture in the combustion engine does not move down to the crankcase and causes low compression and power.

engine oil in the crankcase, used for lubrication, does not move up into the combustion chamber and gets burnt.

2. wiper ring: clean the liner surface off the excess oil and to act as support backup ring on stopping any gas leakage further down which escaped the top compression ring.

3.oil ring is used to wipe excess oil from the cylinder wall during piston movement. Excess oil is returned through ring openings to the oil reservoir in the engine block.

How Motorcycle engine intake and exhaust valves works

control the entry and exit of air and fuel mixture to the combustion chamber. Most modern bikes have four valves per cylinder (two for inlet, two for exhaust).

Crank shaft connected timg

Intake and exahaust volves controlled by timing chain

Camshaft

take care of valve controls

When the Piston goes down opens Intake volves,
When the Piston goes down opens outlet volves,
engine misfires if there is no synchronization between crank & cam shaft

Timing chain connects crank shaft and cam shaft synchronizes both cam & crank shafts

Symptoms Of Bad Piston Rings

Symptoms of bad piston rings are similar to the symptoms of worn or damaged valve seals. Catching symptoms in the early stages will save your engine and save you from a hefty bill. Here is a list of the most common symptoms for bad piston rings:

White or gray exhaust smoke (engine oil burn cumbston chamber)
Excessive oil consumption (Worn-out piston rings will lead to oil leaks in the combustion chamber)
Low power for acceleration
Overall loss of power or poor performance
Oil in the intake manifold

10 hours to complete a piston ring replacement.

Piston engine misfire

Engine misfires happen when one of the cylinders does not produce sufficient spark or compression and lack of fuel. It could involve more than one cylinder. It can be caused by a faulty spark plug, fuel injector, ignition coil and or worn cylinder.