What is meant by 2-stroke engine? What is 2-stroke and 4-stroke? How to work a 2-stroke engine? Which is more powerful, 2 or 4-stroke? Why 2-strokes are better than 4-strokes? This content reveals all about the 2-Stroke Engine including meaning, function, principle, purposes, advantages, disadvantages, and more.
What is Meant by 2-Stroke Engine?
A two-stroke engine is a type of internal combustion engine. You may also call it a two-stroke cycle of an engine. The completion of the power cycle takes place with two strokes of the piston. Indeed, the piston goes through one up and one down movement in this system. The alluded procedure takes place within one revolution of the crankshaft.
What is the Principle of a 2-Stroke Engine?
In such types of engines, the finishing of the combustion stroke and the beginning of the compression stroke are simultaneous. Thus, the intake and exhaust functions occur at the very same time. The power cycle features 2 piston strokes in 1 crankshaft revolution. The process converts fuel into motion with two strokes: one up and one down movement. The piston lifts up and pulls a mixture of air, fuel, and oil. An intake valve passes those to the crankcase and this is the Compression stroke. Also, the compression of the air-fuel-oil mixture takes place in the combustion chamber at the very same time.
Another stroke is the power stroke. It sees combustion retracting the piston. This process brings in more air-fuel-oil mixture into the combustion chamber. However, the intake valve closes during this stroke. At the same time, it ensures that the exhaust in the combustion chamber expels through an exhaust port.
What is Use for 2-Stroke Engine?
You will mostly see such engines in smaller & lower-power engines or vehicles. That includes scooters, dirt bikes, jet skis, smaller outboard motors, etc. You may also see it on lawn equipment, for ex: lawnmowers or chainsaws.
Why are 2-Stroke Engines Better?
2-Stroke engines provide some key advantages to the users. Its pros include:
- Able to deliver a higher power-to-weight ratio than 4-stroke engines.
- The manufacturing cost is lower of these engines.
- They are also light-weight than their counterparts.
What are 3 Disadvantages of 2-Stroke Engines?
There are some cons of the 2-stroke Engines. The major disadvantages of this engine are:
- Unable to produce more torque at lower rpm, unlike the 4-stroke engines.
- They are high-revving and have less durability.
- The fuel efficiency is also lesser than the 4-stroke engines and relatively emits more.
Which is Faster, 2 or 4-Stroke?
Relatively, a 2-stroke engine is faster than its counterpart. Because it finishes a power cycle with every crankshaft revolution. Thus provides power delivery more quickly. Thus it is able to offer a rapid acceleration.
Which Engine is Better, 2-stroke or 4-stroke?
Take a look at the key differences of the 2 types of engines.
| 2-Stroke Engine | 4-Stroke Engine |
| Features one full revolution of the crankshaft. | Requires two full revolutions of the crankshaft. |
| Two piston cycles complete the entire combustion event. | Four-piston cycles complete the intake, compression, power, and exhaust strokes |
| Intake-ignition strokes take place at the same time while Compression-Exhaust Strokes also occur simultaneously. | All 4 strokes take place differently, one after another. |
| Relatively faster as it is able to provide instantaneous power delivery and acceleration. | A bit slower with a late power delivery and acceleration due to more number of strokes. |
| Suitable to take start to start in cold temperatures. Thus appropriate for use in snowmobiles. | Doesn’t suit much to start in cold temperatures. |
| Delivers a higher power-to-weight ratio. | Can’t provide a higher power-to-weight ratio. |
| Cheaper option as the manufacturing cost is lower. | Expensive option with a higher manufacturing cost. |
| They weigh less. | 4-stroke engines have more weight. |
| Can’t produce more torque at lower rpm. | Produces produce more torque at lower rpm. |
| High-revving and has a shorter lifespan. | More durable and has a longer lifespan. |
| Less fuel efficient, consumes more oil, and oil cost is higher. | More fuel-efficient and the oil cost is less. |
| Associated with higher emissions. So it isn’t that environmentally friendly. | It emits very low and is environment friendly. |
| Much more common in handheld applications. For example: chainsaws, string trimmers, and backpack blowers. You will see it in scooters, dirt bikes, jet skis, etc. | You will see these engines in motorcycles, ATVs/UTVs, marine motors, and personal watercraft. |
