14
English / USA
FS 90, FS 90 R
USING THE CUTTING 
ATTACHMENTS
For an illustration of the various cutting 
attachments and instructions on proper 
mounting see the chapter on "Mounting 
the Cutting Attachments" in your 
instruction manual.
!Warning!
To reduce the risk of severe or fatal 
injury from blade contact and/or loss of 
control, never attempt to use a metal 
blade on an FS model for which it is not 
authorized.
Using the Mowing Heads
Do not use with mowing line longer than 
the intended length. With a properly 
mounted deflector, the built-in line-
limiting blade will automatically adjust 
the line to its proper length.  
Using the unit with an overly long nylon 
cutting line increases the load on the 
engine and reduces its operating speed. 
This causes the clutch to slip 
continuously and results in overheating 
and damage to important components 
(e.g. clutch, polymer housing 
components). Such damage could, 
among other things, cause the cutting 
attachment to rotate at idle.
Mowing heads are to be used only on 
trimmer/brushcutters equipped with a 
line-limiting blade in the deflector in 
order to keep the line at the proper 
length (see "Parts and Controls" chapter 
in your instruction manual).
If the lawn edges are planted with trees 
or bordered by a fence etc., it is best to 
use a nylon line head. It achieves a 
"softer" cut with less risk of damaging 
tree bark etc. than polymer blades.
However, the polymer-bladed STIHL 
PolyCut produces a better cut if there 
are no plants along the edge of the lawn. 
Sharpening is not necessary, and worn 
polymer blades are easily replaced.
!Warning!
To reduce the risk of serious injury, 
never use wire or metal-reinforced line 
or other material in place of the nylon 
cutting lines. Pieces of wire could break 
off and be thrown at high speed toward 
the operator or bystanders.
STIHL SuperCut mowing head
Fresh line is advanced automatically. 
Frayed line is replaced by a simple 
adjustment (see instruction sheet 
supplied with mowing head).
STIHL TrimCut mowing head 
Frayed line is replaced by a simple 
adjustment (see instruction sheet 
supplied with mowing head).
STIHL AUTOCUT mowing head
Nylon cutting cord advances 
automatically when tapped against the 
ground (TapAction).
000BA015 KN