Suzuki GP125 - Page 10

15
SPECIAL
FEATURES
ROTARY
DISC
VALVE
INTAKE
SYSTEM
Rotary
disc
valve
is
located
between
the
crank
chamber
and
the
carburetor.
When
the
fuel-air
mixture
flows
from
the
carburetor
into
the
crank
chamber,
the
rotary
disc
valve
which
rotates
in
accordance
with
the
crankshaft
closes
and
stops
the
fuel-air
mixture
flow
at
appropriate
timing.
This
valve
operation
makes
it
possible
that
necessary
amount
of
fuel-air
mixture
is
drawn
into
the
engine
of
GP125
and
the
fuel-air
mixture
compressed
in
the
crank
chamber
is
hindered
from
back
flow.
Thus
enough
compression
ratio
is
secured
to
obtain
good
engine
power.
In
case
of
the
ordinary
2-cycle
engine
with
a
piston
valve,
an
inlet
port
is
necessary
on
the
cylinder
wall,
while
in
case
of
GP125,
the
rotary
disc
valve
allows
to
eliminate
this
inlet
Port.
Instead,
GP125
is
provided
with
the
third
scavenging
port
on
that
position.
As
shown
below,
the
fuel-air
mixture
compressed
in
the
crank
chamber
moves
from
the
back
Of
the
piston
through
the
hole
on
its
intake
side
and
enters
the
cylinder
groove.
When
it
finally
flows
into
the
combustion
chamber,
it
pushes
out
the
burned
gas.
By
employing
this
scavenging
system,
scavenging
action
is
carried
out
more
effectively
in
GP125
than
in
the
ordinary
engine,
fuel
consumption
is
decreased
and
yet
enough
power
is
obtained.
Disc valve
L; Disc valve
Disc valve opening
Third scavenging port