Stihl 090 Instruction Manual / Owners Manual page 12

.
...
..-
~
.
Many factors influence the occurence and force of the
!kickback reaction. The
~
of bar and saw chain you
~
~
is a factor in the force of
ttie-klCkback
reaction.
; The speed of
~ ~wh"
the cutter contacts the
object. .,' _
~" <.~,
),' -'_'. ". -
,Kickoaclfforces'Inereuewlth the raleOf Impact·
i l
> \::..:
_"M~:
','
,'i-
~ ''''-''f
~_ct~~
u.;
~ose
of
the
b,ar
and
the
~fo.~·{see-IIt-11).'.-
' : ,.: ' ".'
KickbaCltVmosfproriOunc:ed '"1M upper
quadrant of the
~bar
ROSa, ,,'.'
SOme
STlHL
chain types are designed to reduce kickback
forces.
The.cJeptb.aauges:'
Improper lowering of the depth gauges also
Incre~
the
chanceofa~
:1
The sharpening condition:
warning!
Adun orimproperty sharpen.ed
~
may Increase the risk
of kickback.
Always
cut with a property sharpened chain .
",
Devices for reducing the risk of Idckback
Injury
STlHL has
developed
a chain stopping system to reduce
the risk of injury In certain
kickback sItuations.Jt ~
called a
Quickstop.
""
.,
The, ,Quickstopis,
av-.i~
as an
optiQn
on most STIHL
chain.saws. ' .
Wti .
a~ oc:curs
the
guide.bar
may
iotate
around
the front handle. H the cutting position Is such that the
operatOr's
left hand is
gripping
the
froI1t
hBrldle behind
the
hand
guard,
and if the left hand rotates around the front
handle
and
contacts the front: hanef
guard,
which is the
,Quickstop activating lever,. this contact will activate the
. Quickslop
and,~ the;chaln'(~
ill 13). '
\ The
~.brake
of
some
STlHL
chain
saws
is additional
. self-activated by fnertia.·
see
appropriate.
ct1apler
"ChaIn
Brake"dt
yo~r
<?wner' s
ManuaL ' , ,
, Kickback tendency increases as the radius or size
of
the
guide bar, noseAncreaseLSTIHL
has
developed
guide
bars with small nose radius. These bars. are designed
to
reduce the kfckback tendency and are available, as an
option.
STlHL taas~ d~~
chains
whoseconftgu,r~
are
~ned.to reduce.~
forces. These.
chains
are
available as an option. .
Warning!
Chain
saw
kickback may cause serious or fatal 'injury. To
reduce
the
risk
of
kickback
injuries
snHL'recommends
that you equip
your
saw·With
a
narrow),ose
bal,
lOW
profile
chain or oth8r chatn deSIgned to reduce
'kickback
forces,
.. ~aS11HL~.
Warning I
~o
Qulcksk;Jp
or ch~ ~ de~
.prev&n!SkIckback.
These devices are designed only to stop the chain. if acti-
vated, in. certain kickback
situations.
In
~r
for the
Quickstep to
reduce the
riSk
of
' k iCkback
inj~,
it
mUst
be P"'~ mai~
anei'ln gOod working
order. In addition, there must be enough distance between
the bar and the operator
to
ensure that the Quickstop has
sufficient time to activate and stop the chain before poten-
tial contact with the operator. '
11