What Is the MS 290’s Recommended Bar Range (Bar Sizing)

The STIHL MS 290 is commonly used with 16-, 18-, or 20-inch guide bars. Treat 16–20 inches as a practical range, not proof that any bar will fit: match the bar mount, chain pitch and gauge, drive-link count, and sprocket to your saw. Check its manual and existing parts before buying or installing a replacement.

If a manual or parts listing gives you several bar lengths, it can be hard to know which one to choose. The short answer is that a longer bar is not automatically better. Pick a length that suits the wood you cut, your control of the saw, and the exact parts fitted to your MS 290.

MS 290 Bar, Chain, and Safety Setup

The MS 290’s common guide-bar choices are 16, 18, and 20 inches. A bar in that range is suitable only if its mounting end and chain specifications match your individual saw. Before buying, check the manual, the bar markings, and the saw’s drive sprocket markings.

The MS 290 has a 56.5 cm³ engine. That figure describes engine displacement, not a guarantee that every bar length or chain type will work on every saw. The commonly listed bar range is 16–20 inches (about 40–50 cm), with 20 inches at the upper end.

The best choice depends on the cuts you plan to make and the parts already on your saw. An 18-inch bar may be a reasonable middle choice if it is approved for your configuration, but it is not a universal “best” length. A longer bar adds reach, but does not make cutting safer or prove the saw is suitable for a particular tree or task.

What must match when replacing the bar

A guide bar is the long metal guide that supports and directs the chain. Its length is only one part of fit. The bar must also fit the saw’s mounting area, and its groove must suit the chain.

Chain pitch is the spacing between the chain’s drive links, while gauge is the thickness of those links where they sit in the bar groove. The sprocket, chain, and bar must use matching specifications. The number of drive links must also be right for that specific bar.

• Bar mount: Check the bar’s mounting pattern against the saw. A bar with the wrong mount may not attach properly.
• Pitch: Match the chain pitch to the bar and drive sprocket. Some MS 290 setups are listed with 3/8-inch pitch and .063-inch (1.6 mm) gauge, but do not rely on that as a universal specification.
• Gauge: Confirm the chain’s drive-link thickness matches the bar groove.
• Drive-link count: Use the count specified for the exact bar and chain combination. It can change with bar length and design.

Read the markings on the bar and sprocket, then confirm them in the saw’s manual or with a qualified dealer. Do not buy a chain based on bar length alone. If the parts’ specifications conflict or cannot be read, pause and identify the saw’s exact configuration before fitting anything.

Basic safety check before fitting and cutting

Personal protective equipment (PPE) means gear designed to reduce injury risk. Wear chainsaw-rated head, eye, and hearing protection, leg protection, gloves, and suitable boots. Follow the saw’s manual and applicable local safety rules; keep bystanders clear and plan a safe way out of the cutting area.

With the engine off, inspect the bar, chain, chain brake, throttle lockout, and chain catcher. Make sure the chain is correctly tensioned and can move freely by hand while wearing gloves. Fill the chain-oil reservoir and use the specified fuel mix; the MS 290 manual calls for a 50:1 gasoline-to-two-stroke-oil mix. Start the saw using the manual’s method, with the chain brake engaged and the saw on stable ground.

A longer bar exposes more of the chain near the nose. Contact between wood and the upper quadrant of the bar nose can cause severe rotational kickback. Keep that area clear of wood and other objects, hold the saw with both hands, and do not use a longer bar to reach beyond a controlled position.

Field Cutting and Landscaping Operation

Bar selection affects reach and handling, but it does not replace sound cutting technique. Choose a compatible length that gives you enough reach for the planned cut while keeping the saw under control. If a tree is under tension, hung up, or requires complex felling, stop and get help from a qualified person.

A shorter bar may feel easier to manage for smaller cuts, while a longer one can reach farther. Those are practical considerations, not a promise that either bar is right for every operator or job. The manual’s approved range and your exact bar-chain-sprocket match come first.

Illustrative fitment scenarios—not reports of specific installations:

• Replacing a 16-inch setup: If the existing bar is damaged, use its markings and the manual to identify the mount, pitch, gauge, and chain count. Do not assume a new 16-inch bar will take the old chain.
• Moving from 16 to 18 inches: Confirm that the saw configuration allows the change and identify a chain with the correct drive-link count. A bar-length change can require a different chain.
• Considering a 20-inch bar: Treat this as the upper end of the commonly listed range. Confirm approval for the saw, all matching parts, and your ability to control the saw for the cut. More reach is not a reason to cut from an unstable position.

For any setup, release the chain brake only when ready to cut. Keep secure footing and use a two-handed grip. Do not force a dull chain through wood or continue if the brake, chain tension, or lubrication system is not working properly.

Maintenance, Sharpening, and Carburetor Service

Regular checks help the bar and chain run as intended, but they cannot correct a mismatched setup. Keep the chain sharp and properly tensioned, and make sure the oil system supplies lubrication. Use the manual for inspection and service steps; seek qualified service if a safety device or engine setting needs repair.

After shutting the saw down, let it cool before cleaning or checking it. Follow the manual’s directions for chain tension, since a chain can change tension as it heats and cools. Clean the bar groove and oil passage as directed, and inspect the bar and chain for wear or damage.

If chain lubrication seems poor, stop using the saw and check the oil level and the manual’s troubleshooting steps. Do not keep cutting with a dry or poorly lubricated chain. Carburetor adjustments affect engine operation, not bar fit; use the model’s service information or a qualified technician rather than tuning by ear or exceeding specified limits.

Storage and Seasonal Care

Before storing the MS 290, engage the chain brake, shut the engine off, and let the saw cool. Clean and inspect the bar and chain, then follow the manual’s fuel and storage instructions. Safe storage protects the equipment and helps you spot a worn or damaged part before the next use.

Keep the bar and chain protected from damage, and store the saw where children and unauthorized users cannot reach it. If you remove the bar for cleaning or storage, keep its identifying markings with the parts so you can confirm the correct chain and fitment later.

Conclusion and FAQ

For the MS 290, 16, 18, and 20 inches are the commonly specified bar lengths, with 20 inches at the upper end. The right bar is the one approved for your saw and matched to its mount, chain, and sprocket. Confirm those details in the manual and on the parts before installation.

What is the recommended bar range for a STIHL MS 290?

The commonly specified range is 16–20 inches, often listed as 16-, 18-, or 20-inch bars. Check your saw’s manual and parts before choosing a replacement.

Is a 20-inch bar too long for an MS 290?

A 20-inch bar is commonly listed at the upper end of the range. It is not suitable by length alone; confirm the saw configuration, matching parts, and your ability to control the cut.

Is an 18-inch bar a good choice?

It can be a middle option when approved for your saw and matched to the correct chain and sprocket. It is not automatically the best choice for every job.

Can I put any 16-inch bar on an MS 290?

No. The mount, chain pitch, chain gauge, and drive-link count must match the saw’s configuration. Check the manual and bar markings.

Does a longer bar need a different chain?

Often, yes. The drive-link count depends on the specific bar and chain design. Confirm the correct chain specification rather than relying on bar length alone.

What chain pitch does an MS 290 use?

Specifications can vary by configuration. Some setups are listed with 3/8-inch pitch, but verify the pitch marked on the sprocket and bar and specified in the manual.

What does chain gauge mean?

Gauge is the thickness of the chain’s drive links where they fit inside the bar groove. The chain gauge and bar groove must match.

Can I use the same chain when changing bar length?

Only if the chain’s drive-link count and other specifications suit the new bar. Check the bar and chain markings or the manual before installation.

How do I know whether a replacement bar fits?

Confirm the bar mount and the matching chain pitch, gauge, and drive-link count. If the markings are unclear, ask a qualified STIHL dealer to identify the setup.

Does a longer bar make the saw safer for large cuts?

No. A longer bar adds reach but does not make a cut safer or the saw better suited to the work. The upper quadrant near the bar nose can cause severe kickback if it contacts an object.

(This article was written by one of our staff writers, Evan Bradley. Visit our Meet the Team page.)