STIHL FS 91 R

Last updated: October 31, 2026

STIHL FS 91 R
3.2/5#15 of 15 in gas string trimmers
3.2

For acreage, ditches and thick weeds where a 27 cc trimmer bogs down. Too heavy and costly for an ordinary yard.

  • 16.5 inSwath
  • .105 inLine
  • 12 lb (dry)Weight
  • 2 yearsWarranty
Check price at STIHL$379.99

Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.

Pros
  • 4-MIX engine has the most torque of the STIHLs here for thick, wet growth
  • Large 24 fl oz tank runs longer between fill-ups
  • Solid drive shaft and takes heavy .105 in line
Cons
  • Heaviest STIHL here at 12 lb before the head and guard
  • Still needs mixed fuel despite the four stroke design
  • Not sold in California

How it scores

The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its power source. How we rank explains each one.

Specifications

Model number41802000506US
Cutting
Cutting swath16.5 in
Largest line.105 in
Line feedBump feed
ShaftStraight
Converts to edgerNo
Takes attachmentsNo
Power
Engine or battery28.4 cc, 4-stroke
Build
Weight12 lb (dry)
Warranty2 years

Alternatives in this power source

STIHL FS 38
#13 in Gas3.3Full review

A small, light gas trimmer for tidying the edges of a typical suburban lot. Buyers with thick weeds or long fence lines should look at a straight shaft model.

STIHL $219.99
$219.99

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