Arctic Cat Panther 1974 Manual page 122

THEORY OF OPERATION
Weights, Rollers and Ramps
The weights and rollers are bolted to arms that are
pinned to the spider, Fig. V-1. The spider is
equipped with 3 arms, each arm having 2 weights
and a roller with bushing that are retained to the
arm by a small bolt and locknut, Fig. V-1. The
complete spider assembly (includes arms, weights
and rollers) is fastened to the stationary sheave
shaft by means of 3 set screws and a split ring.
The function of the weights is to provide an
outward force against the spring while the rollers
roll on 3 ramps. The 3 ramps are so designed that
clutch engagement will be smooth and the total
shift pattern be responsive to various load factors.
When the engine is at idle (less than clutch
engagement RPM), the force produced against the
ramp by the rollers and weights is not enough to
overcome the spring's preload. As engine RPM
increases and predetermined dutch engagement
speed is achieved, the weights are thrown outward
by centrifugal force caused by increased crankshaft
RPM. At this time, belt engagement occurs because
the moveable sheave moves toward the stationary
sheave causing side pressure on the belt, resulting
in power transmission.
As engine speed gradually increases to peak horse-
power RPM, centrifugal force throws the weights
with rollers progressively outward along the angle
of the 3 ramps, Fig. V -1. A ramp that has a steep
angle, Fig. V-1 A, will take more time and engine
RPM to shift from engagement speed through the
complete shift pattern. Conversely, if the ramp
angle is decreased, Fig. V-1A, it will take less time
and engine RPM to shift from engagement speed
through the complete shift pattern. When maxi-
mum RPM are reached and if the track has only a
V-6
slight load, the weights will spin fast enough to
move the belt out to the maximum radius between
the drive clutch sheaves. When the belt is at the
maximum radius, there will be a 1: 1 ratio between
the drive clutch and driven pulley. Top speed will
now be achieved, provided all other systems are
operating properly.
II Note: A light weight will increase clutch
engagement RPM and take longer to complete
the total shift 'pattern. Conversely, a heavy weight
will decrease clutch engagemenet RPM and take
less time to complete the total shift pattern.
Fig. V·1
Fig. V·1A
Steep
Angle
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