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FS 91

FS 91
A professional bike-handle trimmer with simplified starting, improved air filtration and 30% longer run time than the FS 90.

Model Features

  • 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

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

    More information

  • Cutting Heads & Blades Selection Chart
    Need help selecting a cutting head or blade for your STIHL trimmer or brushcutter?

    Click here to view the Cutting Heads & Blades Selection Chart (PDF Format).
  • Bike Handle
    When used in conjunction with a harness, the bike handle allows the machine to be easily guided, enabling a smooth horizontal mowing action to cover large areas quickly and efficiently. With soft grips for increased comfort, the bike handle provides greater control and helps reduce operator fatigue.

    See it in action!
  • 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.
  • Multi-Function Control Handle
    Having easy access to all of the controls on one comfortable handle makes it easy to complete tasks so the operator’s hand never has to leave the handle.
  • Tool-Free Handle Adjustment
    The central wing nut enables easy adjustment without the use of tools. For transportation and space-saving storage, the handle can be rotated 90°.
  • Purge Pump Primer
    By pressing the bulb, this small fuel pump delivers fuel to the carburetor, reducing the number of starting pulls needed after an extended break between uses.
  • Upright Translucent Fuel Tank
    Allows operator to easily check fuel level before starting work. Upright position makes it easier to refill.
  • Protected Spark Arrestor Muffler
    Has large baffles which reduce noise level and contains a screen designed to reduce the emission of sparks.
  • Protected Spark Plug
    Protected yet easy to change.
  • Heavy-Duty Steel-On-Steel Clutch
    Centrifugal clutch is designed to reduce slippage.
  • Protected or Enclosed Control Cables
    Eliminate dangling and loose wires.
  • Air Filter Cover
    Easily removed for fast and easy filter cleaning or replacement.
  • Throttle Trigger Interlock
    Must be depressed before the trigger can be activated.
  • Start/Run/Stop Controls on Handle
  • Protected Choke Lever/Knob
    Helps prevent damage.
  • High Tech Polymer Housing
    Housings are lightweight, withstand greater impact and are corrosion-resistant.
  • Fully Lined Drive Shaft
    Provides smooth operation and less vibration.

Specifications

DISPLACEMENT
28.4 cc (1.73 cu. in.)
ENGINE POWER
0.95 kW (1.27 bhp)
WEIGHT*
5.8 kg (12.8 lbs.)*
FUEL CAPACITY
710 cc (24.0 oz.)
POWER SOURCE
Gas
*Without deflector and cutting attachment.

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.

Reviews

FS 91 is rated 4.7 out of 5 by 9.
Rated 5 out of 5 by from Quality and price The weedeates I bought are top notch and gets the rough jobs done with time to spare!
Date published: 2017-07-06
Rated 4 out of 5 by from Good product I bought this for my lawn business and it seems to be pretty good. It starts right away after doing all the start up procedure. The only reason I rate 4 stars is because I bought this to last a lot of hours and I have no proof of this yet so I will change review after some time has passed also the product guide was not clear on how to restring it but once I figured it out it was a piece of cake. Overall good experience so far.
Date published: 2017-05-25
Rated 5 out of 5 by from Sthil Fs 91 Love my new sthil fs91 very impressive weedeater lots of power easy to use very light and first of all thanks for my sales person Michelle from rainbow ag in Lakeport Ca thanks for recommending the sthil fs91 never been happy Best weedeater ever I highly recommend this product hats off to sthil great job
Date published: 2017-05-25
Rated 5 out of 5 by from Awesome job with blade at cutting small scrub brush. Had a FS 66 for over 40years and decided time to replace it. Have a FS40 for around the house that works great for grass trimming but needed a straight shaft to do heavy brush cutting. Had to take several breaks while using it. It worked harder than I wanted to. Would buy this product again, maybe in another 40years? Still have a very dependable 028Boss chainsaw I've had for over 40years also, and still us it.
Date published: 2017-05-20
Rated 5 out of 5 by from Still 91 trimmer Great tool very powerful and starts up first pull.
Date published: 2017-05-17
Rated 5 out of 5 by from You feel the quality every time you pick it up. Feels secure, starts like a champ, powerful enough to do more than I need. I'm so glad I took the dealers recommendation. I know it's the last trimmer I'll ever need.
Date published: 2017-05-15
Rated 5 out of 5 by from Stout as a mule Best trimmer that I've ever owned, probably pass it on to my kids and buy new ones when the time comes. Awesome product, STHIL is a name you can trust and is still king of the mountain.
Date published: 2017-05-12
Rated 3 out of 5 by from Hard starting and not as powerful as I had hoped First of all, the product is an FS90 - which the review choices say doesn't exist? Maybe that's part of the problem - I have some sort of expired model. Who knows? Followed the starting instructions to a T and will never start using that procedure. Finally took it back to store, where the guy starts it on first pull. I asked him to show me the procedure before he started - nope, just rips the cord and it starts. Well he did it by holding the throttle wide open. NOWHERE IN THE MANUAL DOES IT SUGGEST THAT. After returning home, the same problem continues - the only way it starts is by holding the throttle wide open - product manual is a joke, or this machine is a lemon. I'm not sure which.
Date published: 2017-04-29
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Standard Features

  • Common Features for Trimmers
    View the features common to many STIHL trimmers.

You Will Also Need

For Your Safety

Support

Read what our customers say about STIHL Trimmers
STIHL Trimmers & Edgers, the Right Tools for the Job - Video
How to Wind a STIHL Trimmer Head - Video
Cutting Heads & Blades Selection Chart (PDF)
FS 91 Instruction Manual (PDF)
Download Instructions on How to Rewind Your Trimmer Head (PDF)
Product Safety Manual (PDF)
STIHL Limited Warranty
Contact Us

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