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How ATV Engines Work: Complete Guide

How ATV Engines Work: Complete Guide

ATV engines are very similar to most vehicles. There are a couple of options, but both run with gasoline and various components to reach a designated fuel-air ratio. If you’re an ATV enthusiast or want to know more about vehicle engines, you may be wondering how ATV engines work.

ATV engines work by pulling oxygen and fuel into the combustion chamber, allowing the piston to push upward and combust the mixture. There’s a controlled explosion that propels the vehicle forward or backward, releasing exhaust through the outlet. ATVs come with two-stroke and four-stroke engines.

Throughout this article, you’ll also learn the following information about how ATV engines work:

  • Details about two-stroke and four-stroke engines in ATVs
  • A step-by-step explanation of the whole process from start to finish
  • Tips to keep your ATV’s engine running for a long time, regardless of its type

Types of ATV Engines

ATVs use two-stroke or four-stroke engines. Knowing the type of engine in your ATV will allow you to maintain and operate it much easier. They work very similarly, but there are a few differences worth noting. Let’s break down the details of each engine below.


Two-stroke ATV engines are less efficient since they create power every time the piston hits the combustion chamber.

However, this process provides a bit more power and weighs much less than a four-stroke engine. There’s also no oil reservoir, which means less maintenance and more time to enjoy your investment.

Here’s an animation showing how a 2-stroke engine works:


Four-stroke ATVs require regular oil changes to lubricate the engine. They’re known to be much more reliable than two-stroke engines since they can operate at lower RPMs, reducing wear and tear on the four-stroke.

Furthermore, you don’t have to spend time mixing the oil and fuel every time you add gas to the engine.

  • Both engines are excellent in their own right.
  • Four-stroke engines provide long-lasting reliability, fuel efficiency, and low-RPM power to tear through rough terrain.
  • Two-stroke engines don’t require an oil reservoir and can accelerate incredibly quickly.
  • There’s no doubt both engines have pros and cons, so neither is better than the other.

Here’s an animation of how a 4-stroke engine works:

It’s essential to remember each engine has a unique process, but there are similar elements. For example, they both cause combustion and require most of the same parts throughout the process.

However, two-stroke engines require oil mixed with fuel beforehand, whereas four-stroke engines have a separate reservoir for oil and fuel.

Knowing how your ATV’s engine operates will allow you to keep it running strong. If you’re shopping for an ATV, keep the previously mentioned benefits in mind to aid your decision.

Those of you who want to know the step-by-step process of ATV engines, from ignition to exhaust release, proceed to the next section.

How All-Terrain Vehicles Start

If you know how two-stroke and four-stroke engines operate in other vehicles and motorized equipment, ATVs work the same way.

There’s no deviation in the process since the engine remains the same. Anyone who’s not familiar with engine operations should read the following guide to know more about their ATVs (and other vehicles!).

Here’s how an ATV engine works:

  1. Fuel is brought in through the fuel pump and sprayed into the combustion chamber. The fuel pump and injectors are responsible for pushing enough fuel to match the intake valve’s oxygen. When the proper ratio is achieved, it creates clean energy. However, if there’s an error on either side, it can cause misfires.
  2. The crankshaft raises the piston into the combustion chamber to meet the fuel-oxygen mixture. Once the fuel and air flow through, the piston pushes up and compresses them. Since there’s not much space in the combustion chamber, things heat up pretty quickly.
  3. A small explosion occurs, generating power and propelling the vehicle. shows it takes about half the distance to trigger the oxygen and fuel mixture. Once they explode, there’s a roaring, controlled explosion. This noise is what you hear when you turn on the engine or accelerate.
  4. The exhaust is released to prevent clogs and buildup. Your exhaust pipe blows out the contents, which is why it’s typically covered in a dark soot-colored substance. If you don’t clean the exhaust pipe enough, it can cause all sorts of issues, including overheating. Also, remember to clean the filters to stop clogs that lead to improper fuel-air ratios.
  5. Depending on the engine type, this cycle requires two to four strokes to create power. The main difference between two-stroke and four-stroke engines is how many repetitions it takes to complete the process. As you could imagine, two-stroke engines take two strokes, and four-stroke engines take four strokes.

Learning about all of the parts in the combustion process might be overwhelming. In layman’s terms, fuel goes from the tank to a cylinder that combines with oxygen and explodes from excess pressure. The energy from the control explosion is used to propel the ATV. It’s as simple as that!

Whether you already own an ATV or are shopping for one, knowing how to take care of the engine is essential. If you want a few valuable tips, read on.

ATV Engine Maintenance Suggestions

You’ve probably heard engines are some of the most expensive parts to replace in ATVs. Instead of spending a bunch of money and stressing over an inevitable breakdown, you can try a few helpful suggestions below.

  • Inspect and replace the oil as needed. Remove the oil dipstick on level ground to ensure it’s not tilted. Check it against the required level on the dipstick. Add more if you need to, and don’t forget to look at its color. Dark, chunky, brown oil needs to be replaced as soon as possible to prevent various engine issues.
  • Clean the air filter often. The air filter removes debris from the intake valve, purifying the fuel-oxygen ratio. If it’s not clean, your engine will overheat and burn anything that comes through. As you could imagine, it’s a very dangerous situation. Luckily, air filters are relatively inexpensive and easy to clean.
  • Pay attention to all of the fluids. Coolant, oil, gasoline, transmission fluid, and so on—fluids are responsible for cooling and lubricating your ATV. If they’re discolored, dirty, or low, it’s time to replace them. It’s unfortunate how often ATV engines are ruined due to improper fluid maintenance. They’re so cheap, but the damage caused is much pricier.
  • Store your ATV properly. Game and Fish Mag recommends using products to loosen the gasoline before and after long-term storage. If you’re not using it for the winter, the oil and gasoline will coagulate. When you start the engine, it’ll burn up and cause expensive repairs.
  • Use high-quality fuel as much as possible. The difference between low-end and high-end gasoline is astounding. If you plan to own the ATV longer than a couple of years, you should always use the best, purest fuel available. Combined with a clean air filter, your ATV’s engine will last for a long time.


Now that you know how ATV engines work, you can keep your vehicles maintained and in top shape for many years to come. Two-stroke and four-stroke engines are found in lawnmowers, ATVs, and many other motorized tools and vehicles. If you know how they work, ATV engines will feel familiar.

Here’s a quick recap of the post:

  • It’s crucial to know the type of engine found in your ATV.
  • Maintain the engine by monitoring oil levels, replacing parts as required, and cleaning the filter.
  • ATV engines use controlled explosions created by the crankshaft pushing the piston into the combustion chamber.

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