Chainsaw Glossary of Common Terms

2-stroke fuel is a specially prepared mixture of unleaded petrol and 2-stroke oil designed to lubricate and power 2-stroke engines effectively. The fuel and oil are combined in specific ratios, such as 25:1 (25 parts petrol to 1 part oil) or 40:1, depending on the manufacturer’s recommendations. This blend ensures smooth performance by simultaneously providing combustion power and lubrication to the engine's moving parts.

Why is the Ratio Important?

The correct fuel-to-oil ratio is critical for the engine's longevity and performance. A ratio with too much oil can cause excessive smoke, carbon build-up, and poor performance, while too little oil may lead to insufficient lubrication, overheating, or severe engine damage. Always consult your chainsaw’s manual to determine the recommended ratio for your model.

How Does 2-Stroke Fuel Work?

Unlike 4-stroke engines, 2-stroke engines lack a dedicated lubrication system with a sump. Instead, the oil in the fuel mixture serves as a lubricant for the crankshaft, cylinder, and other internal components. As the fuel burns, the oil leaves a thin protective film on these parts, reducing friction and wear.

Pre-Mixed vs. Manual Mixing

Some users prefer to manually mix 2-stroke fuel, while others opt for pre-mixed solutions available at hardware stores. Pre-mixed fuel ensures accuracy and convenience, often including stabilizers to extend shelf life. However, if mixing manually, always use high-quality 2-stroke oil and fresh unleaded petrol for the best results.

Storage and Usage Tips

• Use Fresh Fuel: 2-stroke fuel can degrade quickly, especially when exposed to air or sunlight. For best results, mix only what you plan to use within 30 days.
• Store Safely: Keep the fuel in a sealed, approved container, away from heat sources or direct sunlight.
• Shake Before Use: If the fuel has been sitting, give it a gentle shake to ensure the oil and petrol are well-mixed.

By understanding and correctly preparing 2-stroke fuel, you can extend your chainsaw’s lifespan, ensure optimal performance, and reduce maintenance issues over time.

What is the Bar Chain?

The bar chain is a critical component of a chainsaw, comprising a looped chain fitted around the sprocket and guide bar. It is responsible for the actual cutting action, slicing through wood and other materials with precision and speed. The chain's sharp cutting teeth enable efficient cutting, while its seamless rotation around the guide bar allows for consistent performance during operation.

Key Components of the Bar Chain

• Cutting Teeth: These are the sharp, hooked sections along the chain that perform the cutting. They are strategically shaped and spaced to ensure clean and efficient cuts. Regular sharpening is essential to maintain their performance.
• Drive Links: These links fit into the guide bar’s groove and engage with the sprocket, driving the chain around the bar. They also help guide the chain for smooth operation.
• Tie Straps and Rivets: These connect the individual parts of the chain, providing flexibility and durability.

How the Bar Chain Works

When the chainsaw’s engine or motor powers the sprocket, it rotates the bar chain at high speeds. As the chain moves around the guide bar, the cutting teeth make contact with the material, slicing through it effectively.

Types of Chains

The bar chain comes in various designs tailored for different cutting tasks and user requirements:

• Full-Chisel Chains: These have square-shaped cutting teeth and are designed for fast, aggressive cutting, ideal for hardwood or professional use. However, they can dull more quickly.
• Semi-Chisel Chains: These feature rounded cutting teeth, which are slower but retain their sharpness longer and are more forgiving in dirty or gritty conditions.
• Low-Profile Chains: Commonly found on consumer-grade chainsaws, these chains are designed with smaller teeth for safety and reduced kickback.
• Skip-Tooth Chains: These chains have fewer teeth, making them suitable for longer guide bars and cutting larger wood, as they reduce resistance and require less power.

Maintenance Tips for the Bar Chain

To ensure the longevity and efficiency of your chainsaw, proper bar chain maintenance is essential:

• Sharpen Regularly: Dull teeth not only slow down cutting but can also overwork the engine or motor. Use a sharpening file or tool designed for your chain’s specific size.
• Check Tension: A loose chain can derail, while an overly tight chain may damage the guide bar and sprocket. Use the tensioning screw to adjust it to the manufacturer’s specifications.
• Lubrication: Chainsaws feature an automatic oiler to keep the chain and guide bar well-lubricated during use. Ensure the oil reservoir is filled before operation.
• Inspect for Wear: Periodically inspect the chain for signs of wear, such as damaged teeth or stretched links, and replace the chain if necessary.

Safety Considerations

• Proper Installation: Ensure the chain is installed correctly with the cutting teeth facing the right direction.
• Use a Chain Brake: Many chainsaws feature a safety brake to immediately stop the chain in case of kickback, minimizing the risk of injury.
• Select the Right Chain: Always use a chain compatible with your chainsaw’s guide bar length, sprocket, and intended application.

By understanding and maintaining the bar chain, you can enhance your chainsaw’s performance, ensure safer operation, and maximize its lifespan.

 At Hyundai Power Equipment, we design our chainsaws with high-quality bar chains that deliver exceptional cutting power and reliability, whether for occasional use or professional-grade tasks.

What is a Chainsaw Choke?

The choke is an essential mechanism on petrol-powered chainsaws that aids in starting the engine, particularly when the engine is cold. It works by temporarily restricting the air intake, enriching the fuel-air mixture in the carburetor. By increasing the ratio of fuel to air, the choke ensures that combustion occurs more easily, making the engine easier to start under colder conditions or after periods of inactivity.

How Does the Choke Work?

The choke is usually controlled by a lever or switch on the chainsaw, which has two primary settings:

• Full Choke: This setting significantly restricts the air intake, providing the richest fuel-air mixture. It is used during the first few pulls of the recoil cord when starting a cold engine.
• Half Choke: Once the engine begins to fire or sputter, the choke is adjusted to the half position to allow more air into the mixture, helping the engine stabilize and warm up.

After the engine is running smoothly, the choke is fully opened, allowing the correct fuel-air balance for optimal operation.

When and Why is the Choke Needed?

• Cold Starts: The choke is especially useful when starting a chainsaw in cold weather or after the engine has been sitting idle for a long period.
• Easier Combustion: A richer fuel-air mixture ensures there’s enough fuel for ignition, as a lean mixture (too much air) can

What is a Guide Bar on Chiansaw? 

The guide bar is the long, oblong-shaped metal bar that serves as the backbone of the chainsaw’s cutting system. It is the component around which the chain wraps and rotates during operation. The guide bar not only directs the chain but also provides stability and support, ensuring precise and efficient cutting.

How Does the Guide Bar Work?

The guide bar contains a groove along its edges where the chain’s drive links run. This groove helps to keep the chain securely in place as it rotates at high speeds. The guide bar’s tip often includes a sprocket nose or a roller tip, which reduces friction and allows the chain to move smoothly and efficiently around the bar.

Why Does Guide Bar Length Matter?

The length of the guide bar directly determines the maximum diameter of wood the chainsaw can cut in a single pass. For example:

A 16-inch guide bar can cut a tree or log with a diameter of up to 16 inches in one pass.

A longer guide bar, such as 20 or 24 inches, is better suited for felling large trees or cutting thick logs.

Types of Guide Bars

Guide bars come in various types, each suited for different applications and user needs:

• Solid Bars: Made from a single piece of steel, these are highly durable and ideal for heavy-duty work, such as cutting hardwood or felling large trees.
• Laminated Bars: Constructed from multiple layers of steel, these are lighter and more user-friendly, making them suitable for general-purpose cutting tasks.
• Carving Bars: Narrower bars designed for detailed work, such as wood carving or pruning.
• Roller Tip Bars: These have a sprocket or roller at the tip to reduce friction and heat, extending the life of the chain and bar.

Maintaining Your Guide Bar

Proper guide bar maintenance is essential for extending its lifespan and ensuring safe, efficient operation:

• Inspect the Groove: Regularly clean out the groove to remove debris, as dirt and sawdust can cause the chain to bind or derail.
• Check for Wear: Examine the guide bar for uneven wear, particularly on the rails. If the rails are worn down, they may need to be dressed or replaced.
• Rotate the Bar: To ensure even wear, flip the guide bar periodically so that both sides are used evenly.
• Lubricate Properly: The guide bar relies on adequate lubrication to reduce friction and heat. Make sure your chainsaw’s automatic oiler is functioning correctly and that the oil reservoir is filled before use.
• Align the Chain: A misaligned chain can cause uneven wear or damage to the guide bar. Always check that the chain is properly tensioned and fits snugly in the groove.

Choosing the Right Guide Bar Length

The ideal guide bar length depends on the type of work you’ll be doing:

• Short Bars (12-16 inches): Ideal for light-duty tasks such as pruning, trimming, or cutting small logs. These are often used by homeowners and beginners.
• Medium Bars (18-20 inches): Versatile and suitable for a mix of tasks, including felling medium-sized trees and cutting firewood.
• Long Bars (22 inches or more): Best for professional-grade tasks, such as felling large trees or cutting thick timber. However, they require more skill to handle and may cause greater fatigue.

Safety Considerations

• Kickback Risk: Guide bar length can affect kickback. Bars with reduced-kickback noses are recommended for beginners or general-purpose use to minimize this risk.
• Weight Balance: Longer guide bars can add significant weight to the chainsaw, making it more challenging to handle. Always choose a guide bar length appropriate for your skill level and physical ability.

At Hyundai Power Equipment, our chainsaws are equipped with high-quality guide bars that offer durability, precision, and performance. Whether you’re a homeowner tackling DIY tasks or a professional requiring heavy-duty equipment, we provide a range of chainsaws to meet your needs. 

By maintaining your guide bar and selecting the right length, you’ll ensure optimal cutting performance and a safer, more enjoyable experience.

What is Kickback?

Kickback is a sudden, forceful reaction that occurs when the guide bar of a chainsaw is thrust backward and upward toward the operator. This potentially dangerous event happens when the chain's tip (specifically the upper quadrant, known as the "kickback zone") strikes an object unexpectedly or when the chain becomes pinched by wood during operation. Kickback is one of the most common causes of chainsaw-related accidents, making it essential to understand and mitigate its risks.

What Causes Kickback?

Kickback typically occurs under the following conditions:

• Tip Contact with an Object: When the upper tip of the guide bar comes into contact with a hard surface, such as a knot, nail, or another foreign object, the sudden resistance causes the chain to stop abruptly, transferring force back to the chainsaw and operator.
• Pinching: When the wood being cut closes in on the guide bar and chain, it can pinch the chain, halting its rotation and causing a reactive force.
• Improper Cutting Techniques: Poor cutting angles, lack of chain tension, or using a dull chain can increase the likelihood of kickback.

The Danger of Kickback

Kickback can happen in the blink of an eye, leaving little time for the operator to react. The sudden upward motion of the guide bar poses a serious risk of injury, especially to the upper body, head, or arms. This is why it’s crucial to understand the causes and take preventative measures.

How to Prevent Kickback

While kickback can’t be entirely eliminated, proper precautions and techniques can greatly reduce its risk:

• Use a Chainsaw with a Chain Brake: Most modern chainsaws, including Hyundai models, are equipped with a safety brake that stops the chain instantly in the event of kickback.
• Choose Low-Kickback Chains: Low-kickback chains are designed with specially shaped cutting teeth and depth gauges to reduce the likelihood of a sudden reactive force.
• Avoid Cutting with the Tip: Whenever possible, avoid using the upper tip of the guide bar, as this is the area most prone to kickback. Use the lower portion of the bar for controlled cutting.
• Maintain Proper Tension: A loose chain is more likely to derail or cause kickback. Always ensure your chain is tensioned correctly according to the manufacturer’s specifications.
• Keep the Chain Sharp: A dull chain increases resistance and forces the operator to apply more pressure, both of which can contribute to kickback. Regular sharpening is essential for safe operation.

Use Proper Cutting Techniques:

• Hold the chainsaw firmly with both hands, keeping a secure grip on the handles.
• Position your body to the side of the saw, never directly behind the guide bar.
• Avoid overreaching or cutting above shoulder height, as this reduces control and increases risk.
• Inspect for Obstacles: Before cutting, inspect the wood for knots, nails, or other potential obstructions that could trigger kickback.

Kickback Safety Features on Hyundai Chainsaws

At Hyundai Power Equipment, we prioritize user safety by integrating advanced features to minimize kickback risks:

• Chain Brakes: Our chainsaws are equipped with automatic chain brakes that engage instantly in the event of kickback, stopping the chain to protect the operator.
• Low-Kickback Chains: Many of our chainsaws come with low-kickback chains as standard, designed for safer operation without compromising cutting performance.
• Ergonomic Design: Hyundai chainsaws feature comfortable, anti-slip grips and well-balanced designs to give users greater control, further reducing the risk of kickback.

Why Understanding Kickback Matters

Kickback is a natural hazard of chainsaw operation, but with proper training, regular maintenance, and the use of safety features, the risks can be greatly reduced. By understanding the causes and adopting best practices, operators can work more confidently and safely.

At Hyundai Power Equipment, we design our chainsaws with user safety in mind, providing powerful, reliable tools equipped with features to protect against kickback and enhance overall performance. Whether you're a homeowner or a professional, understanding kickback is key to safe and efficient operation.

What is the Kickback Zone?

What is a Primer Bulb?

• Cold Starts: Press the primer bulb several times (as specified in the user manual, usually 3-6 times) when starting the chainsaw from cold.
• After Refueling: If the chainsaw runs out of fuel and you’ve refilled the tank, the primer bulb helps restart the engine by ensuring the carburetor is filled with fuel.
• After Extended Storage: If the chainsaw hasn’t been used for a while, fuel may not be readily available in the carburetor, making the primer bulb essential for a smooth start.

What is a Recoil Cord?

What is a Throttle Trigger?

How does a throttle lock work?

The throttle lock works in tandem with other safety features, such as the safety brake and anti-vibration technology, to create a comprehensive safety system. By requiring deliberate action to accelerate the chainsaw, the throttle lock helps prevent accidental injuries and fosters safer operation practices.

What is Chain Pitch?

How is Chain Pitch Measured?

Why is Chain Pitch Important?

• 3/8-inch Pitch:

  Widely used for professional-grade chainsaws and heavy-duty applications.
  Provides fast and aggressive cutting performance, ideal for hardwood and large-diameter trees.

• 0.325-inch Pitch:

  Popular for medium-sized chainsaws and general-purpose use.
  Offers a good balance between cutting power and smooth operation, suitable for trimming, pruning, and moderate logging tasks.

• 1/4-inch Pitch:

  Found on smaller chainsaws and electric models designed for light work.
  Provides precise cuts, ideal for carving, small branches, and finer work.

• 3/4-inch Pitch:

  Rarely used and typically reserved for specialized industrial or forestry applications.

Chain Pitch Compatibility

Final Thoughts on Chain Pitch

What is Chain Gauge?

• 0.043 inch:

  Often found on smaller, lightweight chainsaws designed for casual use.
  Provides a lighter chain, which reduces strain on the engine and is ideal for trimming and pruning tasks.

• 0.050 inch:

  The most common chain gauge for medium-duty chainsaws.
  Balances durability and performance, making it suitable for a wide range of tasks, including cutting firewood and felling small trees.

• 0.058 inch:

  Used on larger chainsaws for more demanding applications.
  Provides additional durability for heavy-duty tasks such as cutting hardwood or logging.
• 0.063 inch:
  Found on high-performance chainsaws used in professional forestry and industrial applications.
  Designed for maximum strength and durability under extreme conditions.

What is a Decompression Valve in a petrol chainsaw?

How Does a Decompression Valve Work on chainsaw?

Manual Activation: The operator presses or turns the decompression valve before pulling the recoil cord. This opens a small port that allows compressed air to escape from the cylinder.

Pressure Release: With less pressure inside the cylinder, pulling the recoil cord requires less force, making it easier to crank the engine.

Automatic Reset: Once the engine starts, the decompression valve automatically closes, allowing the engine to function at full compression for normal operation.

Why is a Decompression Valve Important on chainsaw?

The decompression valve provides several key benefits, particularly on chainsaws with larger engines:

Easier Starting: Reducing cylinder pressure minimizes the effort required to pull the recoil cord, which is especially useful for operators with limited upper body strength.

Reduced Wear and Tear: By lowering the strain on the recoil starter mechanism, the valve helps prevent premature wear and damage to components like the recoil cord and spring.Improved 

Safety: An easier startup process reduces the risk of accidental injury, such as recoil-related strain or mishandling the chainsaw during a difficult start.

Chainsaws That Benefit from a Decompression Valve

Large Petrol Chainsaws: Chainsaws with engines larger than 50cc typically benefit most from a decompression valve due to the increased cylinder pressure.

Professional-Grade Models: High-powered chainsaws used in forestry, logging, or heavy-duty applications often feature a decompression valve to enhance usability and reduce fatigue.

Cold Weather Chainsaws: Starting a cold engine in low temperatures can be more challenging, making a decompression valve a helpful addition.

How to Use the Decompression Valve

Using the decompression valve is straightforward: 

Press or Turn the Valve: Before starting the chainsaw, press or turn the valve to open it and release cylinder pressure.

Pull the Recoil Cord: With reduced pressure, pulling the cord should feel much easier.

Let the Valve Reset: Once the engine starts, the valve will automatically close, allowing the engine to operate at full compression.

Maintenance of the Decompression Valve

To keep the decompression valve functioning properly, regular maintenance is essential:

Keep it Clean: Dust, dirt, and resin can build up around the valve, potentially causing it to stick or malfunction. Clean the area around the valve regularly.

Inspect for Wear: Check the valve for signs of wear, such as damage to the seal or spring mechanism. Replace it if necessary to maintain performance.

Follow Manufacturer Instructions: Always refer to your chainsaw’s user manual for specific maintenance guidelines and valve replacement procedures.

Decompression Valve Features on Hyundai Chainsaws

Ease of Use: Hyundai chainsaws with decompression valves ensure a smooth startup process, even for novice users.

Durability: Our valves are engineered with high-quality materials to withstand repeated use and harsh operating conditions.

Reliability: The automatic reset function ensures the valve operates seamlessly without requiring manual intervention once the engine starts.

Common Issues and Troubleshooting

While decompression valves are generally reliable, occasional issues may arise:

Valve Sticking: If the valve becomes stuck in the open or closed position, check for debris and clean it thoroughly.

Air Leaks: A damaged valve seal can cause air leaks, affecting engine performance. Replace the valve if necessary.

Failure to Reduce Pressure: If the recoil cord remains difficult to pull, inspect the valve for blockages or wear.

What is a Spiked Bumper?