In a previous article, I answered the question “Are chainsaw bars interchangeable?”, and explained what determines bar compatibility on a general level. I also promised to return with more specific info for a few selected saw brands.
In this post, I am going to tell you about the compatibility of Stihl guide bars, and how to find bars that fit your Stihl chainsaw. The article in a nutshell is that Stihl guide bars come in 3 different bar mounts and a total of 9 pitch-gauge combinations. To fit, a replacement bar for a Stihl chainsaw should have the same mount type and chain pitch as the saw; the bar and chain should further have matching pitch.
We will next start with a short recap of chainsaw bar compatibility. Then, we will turn to the main topic of this article – Stihl bar mounts and pitches and gauges – and how these determine which bar fits your saw. Although not strictly a compatibility issue, we will also take a look into bar length with Stihl saws, as this an important practical aspect. We will end with a examples of bar fitting to some of Stihl’s most popular models.
NEW: Bar info for a specific Stihl model is best found in my Stihl saw profiles.
Please also check my Stihl bar data page for tabulated info on original Stihl bars as well my list of Oregon bars for Stihl. I also have an article on Stihl-vs-Husqvarna bar compatibility if you are interested in mixing Stihl and Husqvarna bars.
Bar compatibility in brief
You can read more about bar compatibility in general in my previous article. The matching principles are simple, and can be summarized in one paragraph:
To be compatible with a given chainsaw, a guide bar must essentially have only two things: 1) the right bar mount and 2) same chain pitch as the saw. To be further compatible with a certain chain type, a bar should also be matched to 3) the chain gauge.
These matching principles apply to Stihl bars just as to all other brands: when searching for a compatible replacement bar for your Stihl, just look for bars with the same mount and pitch as your saw. Bar length, gauge, brand, kerf, construction, nose profile, etc., are important, but do not affect saw compatibility as such.
What makes the application of these simple rules challenging is that Stihl uses so many different mounts and pitches across their chainsaw product line, all of which are mutually incompatible. This is what we are going to go through next.
1 Stihl bar mounts
At current, Stihl chainsaw and bars use three (3) different bar mounts: the small 3005, the medium 3003 and the large 3002. These are not interchangeable: if your saw has a 3003 mount, so must your bar.
The image above shows you what the large and medium Stihl mounts look like. In the table below, you see which mount each Stihl model uses, the width of the mount slot, and compatible Cannon and Oregon replacement bar mounts.
MS 241, 250, 251
064, 065, 066
MSE 220, 250
gas battery electric
Identifying the mount
To determine the proper mount for a replacement bar for your saw:
- Check the table for the mount type of your saw
If you do not find your model in the table, you can determine the mount yourself using one of the following methods:
- Check the part number of the old bar (if it’s a Stihl). The mount is the first four numbers in the part number stamped on the bar
- Measure the slot width of the old bar and compare to the widths in the table
- If you have no bar that fits, measure the diameter of the bar studs at their root using a caliper – this should be close to one of the slot widths in the table. (Bar studs are the “bolts” that stick out of the saw body and go through the bar slot.)
Finding Stihl replacement bars which have the right mount can be a bit tricky online, since the mount is not usually clear from the bar model name neither explicitly given in the bar specs.
The best way I have found is to check the bar model number carefully before purchase: with original Stihl bars, the first four digits of the model number are the mount code.
2 Stihl pitches and gauges
Stihl guide saws, bars and chains are designed for a total of 6 different chain pitches and 3 gauges. In the current Stihl lineup, these form 7 pitch-gauge combinations, and bars are available in 9 combinations. The combinations are mutually incompatible.
In the table below, I have listed the design chain pitch and gauge options for most Stihl chainsaw models.
|MS 150, 151|
MSA 120, 140, 160, 161, 200
MS 170, 171, 180, 181, 193, 194
MS 201, 211, 250**
MSE 141, 170, 210, 220
MS 240, 250**, 251
MS 261, 271, 291
MS 290, 311…661
MS 880**, 881**
MS 880**, 881**
gas battery electric
Note that the pitches with a “P” suffix designate special low profile chains, that go by the names “Picco”, “Extended” or “LP”. These are not compatible with the regular pitch parts, that is 3/8”P will not fit 3/8” parts (I did make this mistake myself).
Also note: some Stihl saws seem to have been delivered in two different pitches. Examples are at least MS 880, MS 250, and some others in the MS 200 series. Whenever possible, please check your saw pitch from the manual, the bar, or the chain.
Identifying pitch & gauge
There are many ways to find out the pitch of your Stihl chainsaw:
- Use the table above: if you know your saw model number, you can check the pitch from the table above. NB: double-checking with other methods recommended
- Check bar markings: Stihl bars have the pitch and gauge clearly printed on them (unless they have been worn out). If you have the original bar, this will tell you what you need. See image below for an example.
- Check chain markings: Stihl chains have markings that are relatively simple to interpret and will tell you the pitch and gauge.
Matching pitch & gauge
Since there is quite some confusion our there about how saws, bars and chains go together in terms of pitch and gauge, let’s still recap the matching principles:
- The saw, bar and chain all must have the same pitch. In practice, the drive sprocket on your saw determines the pitch of the bar & chain.
- The bar and chain must have the same gauge. (The saw powerhead does not care about the gauge.) You can choose your chains to match the pitch of the bar, or the other way around.
Stihl bar lengths
After discussing Stihl bar mounts, pitches and gauges, we can turn to the biggest remaining aspect of bar size: bar length.
With Stihl chainsaws, bar length is not a compatibility issue as such. Provided the bar has the right mount and pitch, in principle you could put any length bar on any Stihl saw and make it run somehow.
Rather than compatibility, bar length is a question of saw power, practicality and safety; the question to ask is would this bar length make sense on this saw?
I give general guidelines for guide bar length in a separate article. Here I will stick to Stihl’s recommendations.
Stihl has a recommended bar length range for each of their chainsaw models to address these issues. The range is determined mainly by the saw size and power.
Bar length vs. Engine size
The minimum bar length recommended by Stihl is 10” or 12” for small (35 cc and under) gasoline-powered, battery or electric chainsaws, and 16” for medium-sized and large gas saws. I suspect this minimum is related to kick-back safety.
The maximum bar length Stihl recommends for their saws increases roughly linearly with engine size:
- Very small under 30 cc and smallest battery and electric models take a 12” bar at maximum,
- Small 30…35 cc gas, mid-sized electric and large battery saws take a 16” bar,
- Mid-sized 45…50 cc gas and large electric saws take a 20” bar
- Large 60…120 cc saws have maximum bar lengths between 25” and 59”; the recommendations vary a lot
I have summarized minimum and maximum recommended bar lengths in the table below, and added a few Stihl models as examples of each motor size class.
|Motor size [cc]||Examples of |
|under 30 cc||MS 150, 151|
|10” or 12”||12”|
|30…35 cc||MS 170…201|
MSE 170, 210
|45…55 cc||MS 271, 261, 291|
|60…120 cc||MS 362, 661, 881||16”||25”…59”|
I should note that these guidelines are relatively rough, and Stihl’s recommendations do not always go in sync with motor size or power. For example, the MS 500i has a longer max bar than the MS 661, despite the latter having both a bigger motor and more horsepower; the MS 250, on the other hand, has a recommended range of only one length (18”). To be sure, check the recommendations for your particular model.
Stihl bar fit examples
Finding which bars fit your Stihl can be a bit confusing even after reading all of my instructions above.
To make the screening process clearer, we will next take a few of the most popular Stihl chainsaw models as examples. As it so happens, these models are also the ones with a few more catches than average.
NEW: Bar fit info for most Stihl saws in my Stihl saw profiles.
What size bar for MS 170?
The MS 170 is a small but capable 30 cc homeowner saw. According to the first table, the MS 170 has the small 3005 Stihl mount and will therefore clearly take 3005 mount bars.
The second table tells that the MS 170 has a chain pitch of 3/8”P, but the gauge may be either .043” or .050”. Stihl website says PMM3 (.043”) in all regions I checked, but the saw seems to have shipped also with .050” bars. Luckily you can fit the saw with a bar of either gauge, as long as you get the matching chain.
Finally, the Stihl gives 12” to 16” as the recommended bar length range for this model.
The MS 170 takes a 12” to 16” bar with a 3005 mount, 3/8”P (Picco) pitch, and either .043” or .050” gauge.
(A side note: Contrary to the websites, Stihl’s chain identification PDF actually gives MS 170 the pitch 1/4”P. I contacted Stihl, and it seems that the website has the correct info for all regions.)
What bar size for MS 250?
The MS 250 ties with MS 251 as Stihl’s most powerful homeowner saw. Matching a bar to this popular Stihl model is a bit more challenging than usual, since the saw comes in two different pitches.
First, checking the mount table, the MS 250 clearly has the small 3005 mount – in fact, it is the most powerful Stihl with this bar mount.
The pitch & gauge table, however, shows two options for the saw: 3/8”P pitch at .050” gauge or .325” at .063” gauge. Stihl USA currently lists the saw as .325”, but the global site as 3/8”P. Based on this, I’d guess new US models are likely .325” and European ones 3/8”P, but before ordering a new bar, you should definitely check the pitch from the old bar.
The MS 250 carries yet another surprise in recommended bar length range: Stihl websites give the range as one length only – 18”. I am uncertain whether this is as intended, since Stihl’s online bar & chain selector tool gives both 16” and 18” bars, and the fairly similar MS 251 with the same power rating is also given a 16” to 18” bar length range.
The MS 250 takes a 16” or 18” bar with 3005 mount and a pitch–gauge combination of either 3/8”P/.050” or .325”/.063”, the latter more likely in the US.
The updated versions MS 251 and MS 251 Wood Boss are similar in that they also take a 16” or 18” bar with 3005 mount, but have only a single pitch and gauge of .325”/.063”.
MS 271 Farm Boss
The MS 271 Farm Boss is a popular mid-range Farm & Ranch saw. It’s bar compatibility is fortunately more clear cut than that of MS 250 or MS 170, and can basically be read straight from the tables:
The MS 271 Farm Boss takes a 16” to 20” bar with the medium 3003 mount, .325” pitch and .063” gauge.
A note on Stihl bar models
As of 2021, Stihl sells almost all of their guide bars under the Rollomatic tradename. There are really six different lines of Rollomatic bars, ranging from the small “E Mini Light” up to the “Super E”.
The main thing to note here is that the Rollomatic model names indicate different bar constructions and profiles, not compatibility. Specifically,
- not all Rollomatic bars are interchangeable
- not all bars in the same Rollomatic line are interchangeable
Best guides in search for compatible Stihl bars are the part number and specifications, not the model name. See my Stihl bar data page for more info.