2 Stroke Engine Vs 4 Stroke Engine

After deciding the right type of dirt bike according to your different preferences, budget and use. The next step should be what type of engine should be right for you and which type of engine would be better.

Yes I am going to talk about the difference between 2 stroke engine and 4 stroke engine.

As the technology is developing, there are continuous change in the automobiles. By the history of automotive engine design, there are mainly two types of engines based on the combustion types that are powered by gasoline.

  • 2  Stroke
  • 4  Stroke

2 stroke and 4 stroke engines are also called as 2 cycle and 4 cycle engines respectively.

I hope that you have heard of these two terms before. You must have wondered about these two types. These are different from each other. Knowledge about the 2 stroke and 4 stroke engine are necessary for knowing efficiency and maintenance about the bikes.

You must know that 2 stroke engines are not in fashion today. These are no longer produced. 2 stroke bikes do not comply with the environmental laws of many other countries.

These two types of engines are mostly used in off road vehicles such as dirt bikes.

If you want to know what engine oil should be used to keep it in good condition then you must read our article about the best two stroke and four stroke engine oil.

How do combustion engines work and what is a ” Stroke”?

To get the answer of these two questions, you need to understand the basics of engine combustion and types of engine in brief.

In the process of combustion cycle in the dirt bikes, there is a piston moving up and down within the cylinder. Here, we also study about the tdc and bdc. It is related to the piston position within cylinder. TDC means top dead center and BDC means bottom dead center.

There, when a piston moves from tdc to bdc and vice versa is called a stroke. A complete process of gas and air being compressed, combusted, ignited, exhausting is called as combustion revolution. It can also be called as combustion cycle.

Some important aspects of combustion revolution:

  1. Intake
  2. Compression
  3. Combustion
  4. Exhaust

Let’s, discuss on these four topics

1. Intake :- in this process, the piston goes down to the cylinder and transfer the mixture of fuel and air into the combustion chamber of the engine.

2. Compression :- In compression, the piston goes back to the top of the cylinder. In this, the intake valve is closed to compresses the gases in the cylinder.

3. Combustion :- When piston reaches to the to top and compresses the air fuel mixture then spark is generated from the spark plug which ignites the gas.

4. Exhaust :- This is the last process of combustion cycle. After combustion air fuel mixture is burned and it produce the power stroke which pushes the piston back at bottom of the cylinder and the exhaust valve is opened.

Now,lets discuss about what is a 2 stroke engine and what is a 4 stroke engine.

What is a 2 stroke engine

A 2 stroke engine is also known as 2 cycle engine. This engine completes a power cycle in 2 strokes by going up and down movements.

It is a type of internal combustion engine. Moving up and down once completes only one crankshaft revolution. That means power stroke is generated in one crankshaft revolution.

It is completely different from 4 stroke engine. The end of the compression stroke and starting of the compression stroke occurs on the same time by the process of intake and exhaust functions. I have explained the “intake” and “exhaust” function above already.

If you want to get maximum output of the bike and get the highest efficiency then you should go through the article how to make a stroke dirt bike faster.

What is a 4 stroke engine

 a 4 stroke engine is also a type of internal combustion engine. In 4 stroke engine the power cycle is completed in 4 strokes. This type of engine can also be called as 4 cycle engine. A full travel of the piston with the cylinder is called as a stroke.

The four strokes are namely:

1. Intake 2. Compression 3. Combustion 4. Exhaust

Intake is the induction of gases. Compression is the process of compressing and producing pressure on the mixture of air and fuel for further ignition process.

Combustion is the ignition of highly compressed (air and fuel) mixture. And lastly, exhaust worked as outlet. Procedure expels the garbage.

Difference between 2 stroke engine and 4 stroke engine

These two types of engines are totally different from each other. If the piston moves two times then the engine is called as 2 stroke engine and if the piston moves four times then the engine is called as four strokes engine.

2 Stroke Engine

  • It has one revolution  of the crank shaft during the power cycle.
  • It uses ports for fuels outlet and inlet.
  • It generates high torque its engine result in losses thermal.
  • It generates more smoke and shows less efficiency.
  • Requires extra lubricating oil because some of the oil burns with the fuel.
  • More wear and tear occurs
  • Engines of 2 stroke are cheaper and easy in manufacturing
  • Lightweight engines and noisy in working.

4 Stroke Engine

  • It has two revolutions of the crankshaft during one power stroke.
  • It uses valves for outlet and inlet of fuel.
  • It generates less torque.
  • It generates less smoke and shows more efficiency.
  • It requires less lubricating oil.
  • Less wear and tear occurs.
  • 4 stroke engines are expensive because of lubrication and hard to manufacture.
  • Heavyweight engines and noiseless in working.

Pros and cons of 2 stroke engine and 4 stroke engine

Here are a few examples of the pros and cons to both engine designs:

As far as terms of the efficiency the engines, the 4 stroke engines definitely wins the race. This is due to the characteristics that fuel is consumed only one time every 4 strokes.

Four stroke engines are heavier in comparison to two stroke engines ; they weigh higher 50% more than a two stroke engine.

Most importantly, a 2 stroke engine creates more torque at a higher rpm, but a 4 stroke engine creates a higher torque at a lower rpm.

The 4 stroke engine also makes less noise than a 2-stoke engine, and is significantly louder and has a distinctive, high-pitched “buzzing” sound.

Because 2- stroke engines are designed to run at a higher rpm, they also have a tendency of  wearing out faster; a 4- stroke engine is generally more durable than a 2 stroke engine. That being said, 2- stroke engines are more powerful.

Two- stroke engines are of simple design, so that they are easier to fix. They do not have valves, but they have ports. Four- stroke engines have more parts and complex in design, therefore they are more expensive and repairing cost is more.

Two- stroke engines require pre-mixing of oil and fuel, while the 4- strokes do not require this.

Four- stroke engines are more environment friendly; but in a 2- stroke engine, burnt oil is also released into the air by the exhaust (outlet).

Two-stroke engines are majorly found in smaller applications such as remote-controlled cars, chainsaws, boat motors, lawn tools and most commonly dirt bikes.

Four- stroke engines are found in mainly go-karts, lawnmowers and dirt bikes, they are located on the right side up to the typical internal combustion engine in your dirt bike.

So I have explained each types of advantages and disadvantages of 2 stroke and 4 stroke engine now it’s up to you to decide which engine would be good for your bike, and for what use.

Which is better between 2 stroke or 4 stroke engine for dirt bikes ?

So already we have compared the pros and cons of each. Both have some pros and cons.

For beginners of dirt bikes, 2 stroke engines are lighter than 4 stroke engine and also cost is less to manufacture.

In comparison to 4 stroke engine, 2 stroke engines are also easier to repair and manufacture. However, maintenance are required to be done frequently, unless you actively maintain the engine.

4 stroke engines are much heavier and also cost more to manufacture. 2 stroke engines are better than 4 stroke engines in respect of weight and production.

In that sense, if you want to keep costs less while purchasing the dirt bike, it’s necessary that you have to take a proactive approach, ensuring that you regularly maintain its parts. If you opt for a 2- stroke engine, then according to their design, they are easier to fix.

But if you do need to make regular maintenance a priority, they will not last as long as a 4- stroke engine. Understand your engine’s durability and be proactive against issues that can harm your dirt bike!


We have seen the many aspects and discussed the differences between two stroke and four stroke engine. Many advantages and disadvantages are there in using them. If you have any doubt regarding this then you can ask your query in comment section.

I will try to clear your doubt. If you like this post then share this with other riders.