Do you need to know how to measure a Stihl chainsaw bar? Measuring a Stihl chainsaw bar is crucial for selecting the correct replacement bar and chain, ensuring optimal performance and safety.
When you need to replace chainsaw bar components or simply want to know your chainsaw’s specifications, a precise measurement of the Stihl chainsaw bar length is essential. This guide will walk you through the straightforward process of measuring chainsaw bar dimensions on your Stihl saw, helping you identify the correct Stihl bar size for any need, whether it’s for routine maintenance or a necessary chainsaw bar replacement. We’ll cover everything from identifying the bar’s key features to understanding the importance of related measurements like chainsaw chain pitch and chainsaw drive links.
Why Measuring Your Stihl Chainsaw Bar Matters
Knowing your Stihl chainsaw bar’s exact measurement is not just about curiosity; it’s a vital step for several reasons:
- Compatibility: The most critical reason is to ensure you purchase the correct replacement bar and chain. Using a bar that is too long or too short can lead to poor cutting performance, damage to the saw, and even unsafe operating conditions.
- Performance: The right bar length contributes to the chainsaw’s balance and power delivery. An appropriate bar allows the engine to operate within its optimal RPM range for efficient cutting.
- Safety: A correctly sized bar and chain system is fundamental for safe operation. An ill-fitting setup can cause kickback or other hazardous situations.
- Maintenance: Regularly checking your bar’s condition and knowing its dimensions helps in planning maintenance and replacements.
Identifying Key Components of Your Stihl Chainsaw Bar
Before you start measuring, it’s helpful to know the basic parts of your chainsaw bar that influence its size and compatibility:
- Bar Length: This is the most common measurement, typically referring to the cutting length of the bar.
- Gauge: This refers to the thickness of the drive links that fit into the groove of the bar. It’s crucial for chain compatibility.
- Pitch: This is the spacing between the drive links of the chain, which must match the sprocket and bar groove.
- Drive Links: These are the small tabs on the bottom of the chain that sit in the bar’s groove and are powered by the sprocket. The number of drive links is also a key specification.
How to Measure a Stihl Chainsaw Bar: Step-by-Step
Measuring your Stihl chainsaw bar is a simple process. You’ll need a tape measure or a ruler.
Step 1: Safely Prepare Your Chainsaw
- Ensure the saw is off.
- Disconnect the spark plug. This prevents accidental starting while you work.
- Allow the saw to cool down. Chainsaw bars can get very hot after use.
Step 2: Measure the Cutting Length of the Bar
This is the most common measurement people refer to when discussing Stihl bar size.
- Locate the tip of the bar.
- Measure from the tip of the bar straight down to the base where the chain stops. You are measuring the part of the bar that actually extends beyond the saw’s body.
- Do NOT include the mounting area of the bar that attaches to the chainsaw body.
Example: A common measurement might be 16 inches, 18 inches, or 20 inches. This measurement is often the advertised Stihl chainsaw bar length.
Step 3: Identify the Stihl Bar Model (If Possible)
Many Stihl bars have their model number stamped directly onto them, usually near the base where the bar mounts to the saw. This is the easiest form of chainsaw bar identification.
- Look for a series of numbers and letters. This stamp is your most reliable source for Stihl bar model information.
- If you can find this, you can often look up exact specifications online or by consulting a Stihl dealer, which simplifies the process of chainsaw bar replacement.
Step 4: Determine the Gauge of the Bar
The gauge is the thickness of the metal in the bar’s groove where the chain’s drive links sit. This is a critical measurement for matching your chain.
- Visually inspect the bar groove.
- Common Stihl gauges include:
- .050 inches (or 1.3 mm)
- .063 inches (or 1.6 mm)
- .043 inches (or 1.1 mm) – less common for Stihl bars but exists.
- How to measure gauge accurately: While you can often tell by comparing with a known measurement or looking at the chain that fits, the most precise way involves removing the chain and using a caliper to measure the width of the groove. However, for most users, identifying the gauge from existing chain specifications or the bar stamp is sufficient. If your existing chain fits snugly but can still move side-to-side slightly, that’s a good indicator.
Step 5: Determine the Pitch of the Chain (and thus the Bar)
The pitch is the distance between the drive links, measured from the rivet head to the next rivet head, then divided by two. This measurement is critical for the chain to mesh correctly with the drive sprocket.
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Common Stihl pitches include:
- .325″
- 3/8″ (also written as .375″)
- .404″
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How to measure pitch: This is best measured by counting drive links and using a known chain as a reference or by consulting the chain’s packaging or stamp. Measuring it directly can be tricky:
- Count 10 drive links on your existing chain.
- Measure the distance from the front of the first drive link to the front of the tenth drive link.
- Divide that measurement by 9 (since there are 9 spaces between 10 links). For example, if the measurement is 6.5 inches, the pitch is 6.5 / 9 = 0.722 inches. This isn’t the standard way.
* The standard method: Count the number of drive links on your chain that make contact with the bar’s nose sprocket. The number of drive links is directly related to the pitch and the bar length. If you don’t have the chain, look for the pitch stamped on the bar itself (often near the gauge) or on the drive sprocket cover.
Step 6: Count the Drive Links on Your Chain
This is another essential piece of information for selecting a new chain or bar.
- Remove the chain from the bar.
- Count the number of drive links. These are the links with the small tabs that sit inside the bar’s groove.
- The number of drive links is a key component of chainsaw chain pitch identification. For example, a 3/8″ pitch chain for a 20-inch bar might have 72 drive links.
Practical Ways to Get Your Stihl Bar Specifications
If stamping is not visible or you need to confirm details, here are other reliable methods for chainsaw bar identification:
1. Consult Your Chainsaw’s Manual
Your Stihl owner’s manual is the definitive source for your saw’s specifications, including the recommended Stihl chainsaw bar length, pitch, and gauge.
2. Check the Existing Chain
The pitch and gauge are usually stamped on the chain itself, often near the drive links or on the cutters.
- Look for markings like “.325”, “3/8”, “.404” (for pitch).
- Look for markings like “1.3mm”, “1.5mm”, “1.6mm” (for gauge, which is equivalent to .050″, .058″, .063″).
3. Examine the Drive Sprocket
The pitch of your chainsaw is also determined by the drive sprocket. Sometimes, the pitch is stamped onto the sprocket itself.
4. Visit a Stihl Dealer or Reputable Outdoor Power Equipment Shop
If you are unsure about any measurements, taking your chainsaw or the old bar and chain to a professional is the best way to ensure you get the correct parts. They have the tools and expertise for accurate chainsaw bar measurement and chainsaw bar identification.
Common Stihl Bar Sizes and Specifications
Stihl offers a wide range of bars for different models and applications. Here are some common examples of Stihl bar size combinations:
| Bar Length (Cutting) | Pitch | Gauge | Typical Drive Links | Common Stihl Models |
|---|---|---|---|---|
| 12″ | .325″ | .050″ | 45 | MSE 140 C-BQ, MSA 140 C-B |
| 14″ | .325″ | .050″ | 52 | MS 251, MS 271 |
| 16″ | .325″ | .050″ | 56 | MS 251, MS 271, MS 291 |
| 16″ | 3/8″ LP | .043″ | 59 | Farm Boss (older models), MS 211 |
| 18″ | .325″ | .050″ | 60 | MS 271, MS 291 |
| 18″ | 3/8″ | .063″ | 62 | MS 362, MS 391 |
| 20″ | .325″ | .050″ | 64 | MS 291, MS 311 |
| 20″ | 3/8″ | .063″ | 72 | MS 362, MS 391, MS 400 |
| 24″ | 3/8″ | .063″ | 81 | MS 362, MS 400, MS 462 |
| 28″ | .404″ | .063″ | 68 | MS 462, MS 500i |
Note: This table provides common examples. Always verify your specific saw’s requirements.
LP in 3/8″ LP stands for “Low Profile,” which is a lighter-duty pitch often used on smaller, homeowner-grade saws.
Why Matching Pitch, Gauge, and Drive Links is Critical
When you replace chainsaw bar, you absolutely must ensure the new bar is compatible with your existing chain and saw. Mismatched specifications can lead to:
- Chain slipping off the bar: If the gauge is too wide, the chain won’t sit securely in the groove.
- Chain binding or jamming: If the gauge is too narrow, the chain can pinch in the groove.
- Premature wear: Incorrect pitch means the chain and sprocket don’t engage properly, leading to rapid wear on both.
- Poor cutting performance: The saw will struggle to cut effectively.
- Damage to the saw: The engine can be strained, and components like the clutch or sprocket can be damaged.
- Safety hazards: Kickback risk increases significantly with an improperly matched chain and bar.
When to Replace Your Stihl Chainsaw Bar
Even with the correct measurements, chainsaw bars wear out over time. Here are signs it’s time for a chainsaw bar replacement:
- Worn groove: The groove where the chain sits can become widened or uneven due to friction. This can be checked by looking at the chain – if it sits too low in the groove or wobbles excessively, the bar is likely worn.
- Burrs or damage: Sharp edges or burrs on the sides of the groove indicate wear.
- Bent bar: If the bar gets bent, often from hitting rocks or debris, it needs immediate replacement. A bent bar will cause the chain to run unevenly and can be very dangerous.
- Chain jumping off: While this can also be a chain tension issue, a worn bar can contribute to the chain coming off even when properly tensioned.
- Uneven wear: The bar wears more on the bottom than the top. You can often flip the bar to even out wear, but once both sides are worn, it’s time for a new one.
Caring for Your Stihl Chainsaw Bar
Proper maintenance extends the life of your bar and ensures safer operation:
- Flip the bar regularly: Every time you sharpen your chain, flip the bar over. This helps distribute wear evenly on both the top and bottom of the groove.
- Keep the groove clean: Debris and sawdust can accumulate in the bar groove. Use a bar groove cleaner tool to keep it free of obstructions.
- Maintain proper chain tension: A loose chain can wobble and accelerate bar wear. An overtightened chain can cause premature wear on the bar, chain, and drive sprocket. Consult your manual for correct tensioning procedures.
- Lubricate properly: Ensure the automatic oiler is working correctly and that the bar and chain are getting sufficient lubrication.
Frequently Asked Questions (FAQ)
Q1: Can I use a different length bar on my Stihl chainsaw?
A1: While it might be physically possible to mount a different length bar, it is generally not recommended unless specified by Stihl for your particular model. Using a longer bar than recommended can overwork the engine, strain the clutch, and reduce cutting efficiency. Using a shorter bar might offer less reach and different handling characteristics. Always check your owner’s manual for compatible bar lengths.
Q2: How do I know if my Stihl bar gauge is .050 or .063?
A2: The gauge is the thickness of the drive links. .050″ (1.3mm) drive links are thinner than .063″ (1.6mm) drive links. The easiest way to check is to look at the stamp on the bar itself, or on the chain. If you can’t find a stamp, you can compare your chain’s drive links to a known chain or use a caliper to measure the width of the groove or the drive link.
Q3: What does the number of drive links mean for my Stihl chainsaw?
A3: The number of drive links is directly related to the chain’s length and the bar’s length for a specific pitch and gauge. When you buy a new chain, you must match the pitch, gauge, and the number of drive links to your bar. For example, a 20-inch bar for a Stihl MS 271 might require a chain with 72 drive links for a .325″ pitch, .050″ gauge.
Q4: How do I find my Stihl bar model number?
A4: The Stihl bar model number is usually stamped directly onto the bar itself, often on the flat surface near the mounting end. Look for a series of numbers and letters. If it’s not visible or has worn off, you’ll need to rely on measuring the bar length, pitch, and gauge, or check your chainsaw’s manual.
Q5: Is measuring the Stihl chainsaw bar length the only thing I need to know for a replacement?
A5: No, while Stihl chainsaw bar length is a primary factor, you also absolutely must match the chainsaw chain pitch and the chainsaw bar gauge. The number of chainsaw drive links is also crucial for chain selection. Incorrectly matching these specifications will result in poor performance and potential damage to your saw.
By following these steps and paying attention to all the specifications, you can confidently measure and select the correct bar and chain for your Stihl chainsaw, ensuring safe and efficient operation for years to come.