Equipment detail

STIHL FS 91 R Commercial Trimmer

Commercial-duty straight-shaft trimmer with STIHL 4-MIX power and a fast-loading Speed-Feed head.

The STIHL FS 91 R is a commercial-grade trimmer built for residential, commercial, roadside, municipal, and property-maintenance work. Its 28.4cc STIHL 4-MIX engine, solid steel driveshaft, commercial-duty gearbox, loop handle, and Speed-Feed cutting head make it suitable for fence lines, banks, ditches, heavy weeds, parking lots, and general landscape maintenance.

STIHL FS 91 R commercial trimmer
Quick facts

Commercial-duty string trimming performance

  • 28.4cc STIHL 4-MIX engine
  • 1.3 HP
  • Commercial solid steel driveshaft
  • Straight shaft
  • Approximately 16.5-inch cutting swath
  • Speed-Feed head
  • 50:1 fuel mix
  • 12.1 lb dry weight
  • Customer pickup available
  • Delivery available only when bundled with mower and/or blower rental
  • Disposable safety glasses and earmuffs available upon request
Rental rates

Flexible rental options

$50
Daily
$85
Weekend
$125
Weekly
$1,250
Monthly
Specifications

STIHL FS 91 R

ManufacturerSTIHL
ModelFS 91 R
Equipment TypeCommercial Straight-Shaft Trimmer
Engine TypeSTIHL 4-MIX Single-Cylinder
Fuel50:1 Gasoline/Oil Mix
Displacement28.4 cc / 1.73 cu in
Power Output0.95 kW / 1.3 HP
Idle Speed2,800 RPM
Maximum Engine Speed9,500 RPM
Maximum Output Shaft Speed7,150 RPM
Fuel Tank Capacity24 oz / 0.71 L
Dry Weight12.1 lbs / 5.5 kg, without guard or cutting head
Overall Length71 in / 1,800 mm
HandleLoop R Handle
ShaftStraight, Solid Steel Drive Shaft
Cutting SwathApproximately 16.5 in / 420 mm
Harness RingYes
Anti-VibrationYes
Air FilterEasy-Access Heavy-Duty Paper Filter
Engine LubricationMixed Fuel, No Crankcase Oil
Spark PlugBosch USR 7 AC
Valve Clearance0.10 mm Intake and Exhaust
Cutting HeadSpeed-Feed Head
Compatible Line Sizes.080 in, .095 in, and .105 in trimmer line
Features
  • Commercial-duty gearbox
  • Commercial solid steel driveshaft
  • STIHL 4-MIX engine
  • Strong low-end torque
  • Purge bulb for easier starting
  • Manual choke
  • Loop handle for maneuverability
  • Anti-vibration system
  • Easy-access air filter
  • Speed-Feed head reloads without disassembly
  • Line can typically be reloaded in under 30 seconds
Delivery and pickup
  • Customer pickup is available
  • Delivery is available only when combined with a mower and/or blower rental
  • Standalone trimmer delivery is not guaranteed
  • Disposable protective glasses and earmuffs may be provided upon request
  • Final delivery approval depends on distance, scheduling, and the complete rental package
Suitable uses

Recommended use list

  • Residential mowing support
  • Commercial landscape maintenance
  • Fence lines
  • Parking lots
  • Banks and ditches
  • Medium brush
  • Heavy weeds
  • Roadside trimming
  • Municipal grounds
  • DOT-style roadside maintenance
  • General property cleanup
Fueling requirements

Use only the approved fuel mix

  • The trimmer uses fresh approved 50:1 two-stroke premixed fuel
  • The unit must be returned at the same fuel level documented at checkout unless otherwise agreed
  • Straight gasoline must not be used
  • Incorrect fuel or oil mixture may cause engine damage
  • Refueling charges may apply
  • Customer is responsible for damage caused by improper fueling
Cleaning and damage requirements

Return the trimmer in serviceable condition

  • Return the trimmer clean and free of excessive grass, weeds, mud, dust, sticks, string, wire, pet waste, and other debris
  • The cutting head, guard, cooling areas, and air intake must not be packed with debris
  • Cleaning charges may apply if returned excessively dirty
  • Customer is responsible for damage caused by misuse, impacts, improper fueling, blocked cooling airflow, neglect, abuse, unauthorized repair, or improper transport
  • Cutting head, shaft, gearbox, guard, handle, throttle controls, fuel cap, harness ring, and accessories must be returned in the condition documented at checkout
  • The unit may not be sub-rented, loaned, or moved to an unapproved location
  • Final rental approval is required
Safety

Important operating precautions

  • Eye protection is required
  • Hearing protection is strongly recommended
  • Long pants and closed-toe footwear are strongly recommended
  • Keep bystanders, pets, vehicles, windows, and fragile property clear
  • Do not use near loose gravel where thrown objects may cause damage or injury
  • Do not operate indoors or in enclosed spaces
  • Do not use damaged or unapproved cutting attachments
  • Do not remove or bypass the guard
  • Operator must understand and follow all safety instructions
  • Disposable safety glasses and earmuffs may be provided upon request
Frequently asked questions

Common questions

Fresh approved 50:1 two-stroke premixed fuel only.
No. Straight gasoline can damage the engine.
Delivery may be available only when bundled with a mower and/or blower rental.
Yes, customer pickup is available.
A Speed-Feed head compatible with .080, .095, and .105-inch trimmer line.
Disposable safety glasses and earmuffs may be provided upon request.
Yes. Excessive grass, weeds, mud, wire, string, pet waste, or other debris may result in cleaning charges.
It is suitable for heavy weeds and medium brush with the approved installed cutting head. It is not a brush cutter unless equipped and approved for that use.
Only approved attachments supplied or authorized by Priority One Rentals may be used.