FS 91 R - $329.95 DSRP

Distributor Suggested Retail Price
FS 91 R

DSRP: $329.95

A professional trimmer packed with features for simplified and convenient trimming.

Demanding landscapers can save time using the STIHL FS 91 R professional trimmer. With its larger fuel tank than the FS 90 R, this model provides 30% longer run times, as well as a three-step start procedure to get to work faster. Thanks to its superior air filtration and low-emission engine, the FS 91 R is a dependable tool with great maneuverability and power. Its rubberized loop handle is desig...Read More
Print Spec Sheets
FS 91 R Specifications
DISPLACEMENT 28.4 cc (1.73 cu. in.)
ENGINE POWER 0.95 kW (1.27 bhp)
WEIGHT* 5.5 kg (12.1 lbs.)*
FUEL CAPACITY 710 cc (24.0 oz.)
*Without deflector and cutting attachment.
Model Features
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    Reduced-Emission Engine Technology - Caring for Nature
    The STIHL Inc. “Caring for Nature” seal identifies its powered products that are more environmentally conscious, producing zero or low exhaust emissions. STIHL Inc. defines “low exhaust emissions” as being cleaner than EPA and/or CARB exhaust emission standards.

    More Information

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    Built in the USA
    Indicates products that are built in the United States from domestic and foreign parts and components.

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    Shoulder Strap / Carrying System
    Using a shoulder strap or carrying system helps distribute the weight of the equipment for increased operator comfort and improved maneuverability.
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    Adjustable Front Handle
    Adjusts for comfort.
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    Fully Lined Drive Shaft
    Provides smooth operation and less vibration.
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    High Tech Polymer Housing
    Housings are lightweight, withstand greater impact and are corrosion-resistant.
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    Protected Choke Lever/Knob
    Helps prevent damage.
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    Throttle Trigger Interlock
    Must be depressed before the trigger can be activated.
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    Air Filter Cover
    Easily removed for fast and easy filter cleaning or replacement.
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    Protected or Enclosed Control Cables
    Eliminate dangling and loose wires.
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    Heavy-Duty Steel-On-Steel Clutch
    Centrifugal clutch is designed to reduce slippage.
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    Protected Spark Arrestor Muffler
    Has large baffles which reduce noise level and contains a screen designed to reduce the emission of sparks.
Standard Features
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    Common Features for Trimmers
    View the features common to many STIHL trimmers.

Important Information
WARNING! Improper use of any trimmer/brushcutter can cause serious or fatal injury. Read, understand and follow all safety instructions in your instruction manual. To reduce the risk of injury from blade contact, circular saw blades may be used on FS brushcutters that have a limitstop, a bicycle handle and double shoulder harness and not on FS brushcutters with a "J" handle or loop handle. Other rigid blades may be used on FS brushcutters having a bicycle handle, a "J" handle or a loop handle equipped with a barrier bar. To reduce the risk of eye injury always wear proper eye protection. Always use the appropriate deflector for the type of cutting attachment, as explained in your instruction manual.
Note: STIHL engine products with the Caring for Nature logo are cleaner than EPA Standards for exhaust emissions.
Note: STIHL recommends use of fuel with no more than 10% Ethanol content. Using fuel with greater than 10% Ethanol content may cause damage to your equipment and may void your STIHL warranty. Learn More…
WARNING! Improper use of any power tool may cause serious or fatal injury. Read, understand and follow carefully the operating and safety instructions in your instruction manual before using such products.

STIHL products sold through U.S. STIHL Dealers are for distribution in the United States only.
Click to view the STIHL Limited Warranty Time Periods
Optional Accessories
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    Gearbox Attachments
    Gearbox attachments are available for this model. View the interchangeable gearbox chart to find out which attachments work with this model.
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    Trimmer Heads & Blades
    Many trimmer heads and blades are available. Find out which ones to use with this model in this chart.  
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    Trimmer Line
    There's high-performance STIHL trimmer line for every operating condition. 
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    Protect yourself from flying debris while trimming. Check out our selection of deflectors and find the one that will help protect you.
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    Straps and Harnesses
    They distribute the load from your hands to your shoulders. They also help reduce operator fatigue and make it easier to use trimmers, brushcutters and clearing saws for extended periods.
We Also Suggest
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    HP Ultra 2-Cycle Engine Oil
    HP Ultra is a fully synthetic 2-cycle engine oil specially suited for high performance chainsaws and power tools. This oil has outstanding engine cleaning characteristics, plus “ultra” superior lubricating qualities in comparison to other 2-cycle engine oils. It is ideal for use in STIHL 4-MIX® engines. This oil is biodegradable, degrading by 80% in 21 days.

    •2.6 oz. bottle makes 1 gallon mix

    •5.2 oz. bottle makes 2 gallon mix

    •6.4 oz. bottle makes 2 1/2 gallon mix

    •12.8 oz. bottle makes 5 gallon mix

    STIHL recommends a mix of 50:1 high-quality 89 octane or higher unleaded gasoline to STIHL engine oil. This same mix ratio should be used during break-in.

  • No-Spill® Fuel Containers Zoom
    No-Spill® Fuel Containers
    The latest advance in gasoline can technology is here with No-Spill® fuel containers. Featuring a special treated body for low permeation, thumb-button flow controls for easier pouring, and a wide and stable base design to reduce upsets, No-Spill® fuel containers help ensure that the gasoline goes into your tank, not on the ground or into the air. Fill even smaller-sized tanks without spilling – flow stops automatically when the tank becomes full. With 1¼-gallon, 2 ½-gallon and 5-gallon sizes available, you’re sure to find one that fits your needs. Ask your local STIHL Dealer about No-Spill® fuel containers. Don’t settle for anything less.

    Meets California Air Resources Board Phase II requirements for sale or use in California. No-Spill® gasoline cans are tested and certified to ASTM F-852-99 standard specification for portable gasoline containers for consumer use and our diesel and kerosene cans are tested and certified to ASTM F-976-02 standard specification for portable kerosene and diesel containers for consumer use.

For Your Safety
  • STIHL® Pro Mark™  Hearing Protector Zoom
    STIHL® Pro Mark™ Hearing Protector
    Padded stainless steel spring wire headband maintains constant pressure. Easy to adjust. Noise Reduction Rating (NRR): 29. Meets ANSI S3.19-1974 standard.

    Colors available: Camouflage, Orange and Grey
  • Patterned Frame Glasses Zoom
    Patterned Frame Glasses
    Experience professional-grade protection from the harsh sun with the Patterned Frame Glasses from STIHL. Offering 99% UV protection, the glasses meet ANSI standard Z87.1+ and feature comfort-cushioned nose pads and polycarbonate impact-resistant lenses. They’re also lightweight and slip-resistant. Stop by our showroom to check out the Patterned Frame Glasses, as well as all of our protective eyewear!
  • High Performance PRO Gloves Zoom
    High Performance PRO Gloves
    Elastic slip-on cuffs. Padded palm and knuckle guards. Reinforced PVC grip overlays. Sizes: M, L, XL

Are You Ready for a STIHL?

FS 91 R is rated 4.3 out of 5 by 117.
Rated 5 out of 5 by from Excellent My first Stihl Product, i use for residential every 2 week and love the power of this equipment and the build quality is Perfect, but the price in my country little high for this
Date published: 2018-07-28
Rated 5 out of 5 by from Recent Purchase Recently purchased once I returned the high end 4 cycle to Lowe’s. Really love the quality, ease of start, and power. Yes I paid a little more but I believe it will be worth it! We will truly see how it does after sitting this winter.Would highly recommend though.
Date published: 2018-07-26
Rated 2 out of 5 by from There are better options in the same price range Stihl sent me an e-mail asking my to review my purchase since my trimmer (FS 91R) is now one year old, so I decided to oblige them. Before I begin my review, I'd like to state that I have always heard that Stihl was a top brand for reliability, which is what led me to view their products when I decided to retire my old yard equipment, so I purchased a FS 91R string trimmer.The retailer where I purchased it started it up in the store for me and it ran fine. I drove home, which took about 30 minutes, and I could not get the trimmer to start. I was using the same fuel the dealer had initially started it with, so it wasn't a fuel issue. I returned it to the retailer the next day, and they could not get it to run either, so they gave me a brand new one off of the shelf, which is easy to start. The trimmer is well balanced and works okay most of the time, but there are a few issues. When starting the engine from a cold start, it starts easily by the second or third pull, but after the engine has been running for some time, and I turn it off, it is very difficult to start and requires multiple attempts. In this situation, I typically have to hold the throttle wide open while starting the engine, and even then, it takes several tries before it will run. Once it is running, it is fine. There is no choke lever on this machine. It has a rotary knob that you turn to the choke position, and as soon as you apply the slightest bit of throttle, it un-chokes. I would much prefer a manual choke lever. It is difficult to load string onto the trimmer's head, and I will soon purchase and aftermarket head for this unit to make it easier to load string. For the amount of money that this trimmer costs, I feel that there are better options that will outperform the FS 91R. I would not recommend purchasing this trimmer.
Date published: 2018-07-26
Rated 5 out of 5 by from Last one I will ever need ! I waited a few weeks to write this review , mainly because it was sooo very impressive the first day home. Now after catching up on a yard gone wild , three tanks of fuel and only one reload on the line spool (yes , the stihl line is worth it ), I am still impressed at the easy start up and power to perform, even when it is triple digit hot outside. This product line is awesome - i have had many of the other top brands - they do not compare, For any home owner and maybe some small buisines's this model is the text book version of a weed EATER ! Three years of overgrown weeds gone in seconds. I have owned two Stihl chainsaws for years - now I kick myself for not having this machine sooner.
Date published: 2018-07-20
Rated 5 out of 5 by from Great product, and always cranks right up. The Trimmer is a great product, and has a lot of power. It works great for my 4 acres and will not stop even through thick and heavy brush like weeds.
Date published: 2018-07-18
Rated 5 out of 5 by from Great Trimmer This is my 3rd trimmer and I have loved them all. The last one I had a little trouble with the idle and had it back to the shop to fix the low idle and even adjust the high idle. But other than that the trimmer is great for everything from trimming to edging.
Date published: 2018-07-16
Rated 4 out of 5 by from Love this machine. Lots of power, starts right up.The only thing I am not crazy about is the head is a little tricky to release.
Date published: 2018-07-04
Rated 1 out of 5 by from I had a 10 year old 2 stroke model , an FS 89 I think. Buying the FS 91 should have been an improvement. The 4 stroke is significantly weaker. I under I had a 10 year old 2 stroke model , an FS 89 I think. Buying the FS 91 should have been an improvement. The 4 stroke is significantly weaker. I understand that it has more chances for things to go wrong as well. I returned it and went with a different brand. Lighter, stronger, and cheaper. I love the chain saws but stay away from the trimmers !
Date published: 2018-07-01
Rated 5 out of 5 by from Great piece of equipment Great product has lots of power and starts right up. I'll never buy anything other than stihl
Date published: 2018-06-29
Rated 5 out of 5 by from Great trimmer Just a homeowner trimming 3/4 acre, but I’ve owned this trimmer for nearly 5 years. It always starts, has great power and it’s relatively light for its size. I’ve always had great luck with Stihl products. I currently own two pro saws and one farm/ranch saw. One of the pro saws is 20 years old. As long as you take care of it, this trimmer will take care of you.
Date published: 2018-06-28
Rated 2 out of 5 by from Not The Best Pick Unfortunately this is not the trimmer to purchase. With several issues such as unable to feather the throttle and hard starting, I decided to cut my losses and get a different unit. After talking to several people at Stihl, this unit is designed to run two speeds, off and full throttle. As a proscaper, we cannot have full throttle all the time. I suggest moving on to the FS94R.
Date published: 2018-06-27
Rated 5 out of 5 by from Strong trimmer I love this still trimmer starts easy , cuts through thick grass and tall weeds with no power loss! Can’t wait to get a brush blade for it!
Date published: 2018-06-26
Rated 5 out of 5 by from A real trimmer This is my first “real” trimmer it’s got plenty of power and is pretty quiet. The trimmer is a four stroke that uses 50/50 oil gas mix. The strap is a little too short I’m a tall guy. I had to add some links
Date published: 2018-06-26
Rated 5 out of 5 by from Perfect Trimmer Great machine that starts up every time! Powerful and economical, I've used this trimmer for heavy commercial work and it stands the test of time. Much quieter than most trimmers, and the string spool system is super simple. My advice: when in doubt, buy this machine and you'll never regret it. One word of advice though: follow startup instructions or you can flood the engine, making it harder to start.
Date published: 2018-06-24
Rated 1 out of 5 by from Terrible Can’t keep string on machine. It gets very hot on your arm. My old Husqvarna is much better machine.
Date published: 2018-06-19
Rated 5 out of 5 by from Great trimmer with plenty of power for all lawn care needs. Starts easy every time. This is my favorite professional lawn care trimmer. It has the perfect blend of power/performance/balance/reliability for ant lawn care job. Comfortable for extended use. Very little vibration at all operating speeds(best in class)!
Date published: 2018-06-14
Rated 5 out of 5 by from FS 91 R I bought this product this year to replace an old trimmer. It does everything better than my old home depot special if you know what I mean. In addition, I also purchased a new hedge trimming bar with the machine and it's incredible. It saves me so much time on jobs with the edging and have the ability to do bigger hedge jobs. It is truly a win win. I would highly recommend this product to anyone doing more than just their own home. I have used Stihl in the past, but this machine made me a life customer, and since the purchase of the trimmer I also bought a new Stihl (BR600) blower to replace my old one the product is just superior. There is only one downside the weight, but it is worth the trade-off for the power and reliability.
Date published: 2018-06-13
Rated 2 out of 5 by from Carburetor Problems since Purchase I bought my FS91R in Feb18 and have had low and high idle problems e.g. many pulls to start, rough idle, and stalling out during idle and full throttle. I turned it it in to adjust carburetor. I received it back and had it running well and then it would not start. I unsuccessfully attempted to adjust the carburetor myself. I turned it in to replace the carburetor. it was at the service sight for 3 weeks waiting for a carburetor 3 WEEKS. Stihl product are very difficult to find parts for and make repairs. I purchased Stihl for my new business based on their reputation. I will not be purchasing Stihl again.
Date published: 2018-06-11
Rated 4 out of 5 by from Newby review, initial impressions I’m 64, have had various trimmers over the years.My wife and I are building on 8 acres of level pasture with native grasses that will reach eye level. As I will be grass/brush trimming regularly I wanted a quality trimmer with some grunt. This trimmer handles everything with ease so far.My friend who knows his way around tools of all types was impressed that the trimmer handled some of the tall thistle weeds with only the string. I have had no problem with the string breaking or re-winding the spool. Easy peasy.My only complaint so far is the gas tank is too big, you can cut for a long time without stopping.Not cheap so 4 stars, and 3 stars for dependability as I’ve only used it 4 times.Just bought a bigger blade guard and a grass blade. Hope it works well.Easy to start (using motomix)
Date published: 2018-06-10
Date published: 2018-06-09
Rated 4 out of 5 by from Reliable!!! Starts great and runs good but I miss the old school 2 stroke rip! Awesome for everyday around the house stuff plus a lot more, I somehow manage to bog it down in high weeds but that might be my own fault for using a regular grass head when I should be using a brush knife of some sort.
Date published: 2018-06-04
Rated 1 out of 5 by from Cannot wait to return this product Spent most of my time dealing with adjusting the line than actually cutting grass. A goat would have been faster
Date published: 2018-06-02
Rated 5 out of 5 by from Love the product Before I purchased my new Stihl product I read all the reviews I could find, quite frankly I was skeptical about buying, many reviews basically were not good, being that said I purchased anyway, and so far it has preformed great, no problems starting, one pull fires right up, after the brake in period it has plenty of power. I have 4 acres to mow and weed it. I would recommend the FS 91 R to any who askMikeIn Idaho
Date published: 2018-05-31
Rated 5 out of 5 by from Someone always ask, came I help you Have not used much yet, but seems like a beast, works well
Date published: 2018-05-29
Rated 3 out of 5 by from far inferior to previous models I have had fs90r's for years and loved them but the "new improved" fs91r's are a huge disappointment for many reasons. The throttle response is horrible (yes, I have had the throttle adjusted by the dealer) it seems to run soft and then seems to hit a burst of power at half throttle. Feathering the throttle is almost not possible. The "new" design feels heavier in general and does not balance well in the hand. The power head seems much heavier in relation to the trimmer head vs. previous models it is superseding. I am also not a huge fan of the new throttle, it gives the entire machine a "cheap" feel. I do, however, like the new kill button vs the older style sliding switch.
Date published: 2018-05-29
Rated 4 out of 5 by from This trimmer has great power for the size and weight. This trimmer is light and has great power. I have not had time to use it a whole lot but it is easy on string, gas lasts a good amount of time and it is light. I would recommend this trimmer to anyone. I don't have much time on the head so I do not know how it is going to last but besides that I love the machine.
Date published: 2018-05-29
Rated 4 out of 5 by from This is a tractor... This unit is a beast, tractor like low rpm but soooo much torque when I press the throttle the unit rotates in my hand. One word of caution do not prime the bulb it will flood the carboruratior ! So far I’m very satisfied with my unit I will update my review after I use the unit more!!
Date published: 2018-05-27
Rated 5 out of 5 by from Tons of power Tons of power. I lived in a small town and used a cheaper brand that did the job. We moved out in the country and after two times of using it it burnt up. So I went and bought the fs91r and was amazed at what I had been missing out on. When I first cranked it I was like this is the meanest sounding weed eater I have ever heard. Only bad things are it’s a lil on the heavy side and the strap is a good thing but I’m 6’4 and getting the right angle at times with the strap on is a aggravating. But I wouldnt trade it for anything else. I’m waiting on the pole pruner attachment now can’t wait to try it out.
Date published: 2018-05-26
Rated 5 out of 5 by from The dealer Provided excellent service. Very nice trimmer. Put the quick change head on it. Works great. Has power to trim what ever is needed.
Date published: 2018-05-26
Rated 5 out of 5 by from Just bought my second stihl today What can I say just commercial model is nothing but the best!! I've never owned a better weed eater starts immediately and runs flawlessly. And I bought Stihl oil and it doubled my warranty.
Date published: 2018-05-21
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