Polaris RZR 800 2013, Manual

Page: 279 / 500

6
6.5
9924707 - 2013–2014 RZR 800 Service Manual
© Copyright 2013 Polaris Sales Inc.
Driven Clutch Operation
Driven clutches primarily sense torque, opening and
closing according to the forces applied to it from the drive
belt and the transmission input shaft. If the torque
resistance at the transmission input shaft is greater than
the load from the drive belt, the drive belt is kept at the
outer diameter of the driven clutch sheaves.
As engine RPM and horsepower increase, the load from
the drive belt increases, resulting in the belt rotating up
toward the outer diameter of the drive clutch sheaves
and downward into the sheaves of the driven clutch. This
action, which increases the driven clutch speed, is called
upshifting.
Should the throttle setting remain the same and the
vehicle is subjected to a heavier load, the drive belt
rotates back up toward the outer diameter of the driven
clutch and downward into the sheaves of the drive clutch.
This action, which decreases the driven clutch speed, is
called backshifting.
In situations where loads vary (such as uphill and
downhill) and throttle settings are constant, the drive and
driven clutches are continually shifting to maintain
optimum engine RPM. At full throttle a perfectly matched
PVT system should hold engine RPM at the peak of the
power curve. This RPM should be maintained during
clutch upshift and backshift. In this respect, the PVT
system is similar to a power governor. Rather than vary
throttle position, as a conventional governor does, the
PVT system changes engine load requirements by either
upshifting or backshifting.
PVT Break-In (Drive Belt / Clutches)
A proper break-in of the clutches and drive belt will
ensure a longer life and better performance. Break in the
clutches and drive belt by operating at slower speeds
during the 10 hours as recommended (see Chapter 3
“Engine Break-In Period” for break-in example). Pull only
light loads. Avoid aggressive acceleration and high
speed operation during the break-in period.
Maintenance / Inspection
Under normal use the PVT system will provide years of
trouble
free operation. Periodic inspection and
maintenance is required to keep the system operating at
peak performance. The following list of items should be
inspected
and maintained to ensure maximum
performance and service life of PVT components. Refer
to the troubleshooting checklist at the end of this chapter
for more information.
1. Belt Inspection.
2. Drive and Driven Clutch Buttons and Bushings,
Drive Clutch Shift Weights and Pins, Drive Clutch
Spider Rollers and Roller Pins, Drive and Driven
Clutch Springs.
3. Sheave Faces. Clean and inspect for wear.
4. PVT System Sealing. Refer to the appropriate
illustration (s) on the following pages. The PVT
system is air cooled by fins on the drive clutch
stationary sheave. The fins create a low pressure
area in the crankcase casting, drawing air into the
system through an intake duct. The opening for this
intake duct is located at a high point on the vehicle
(location varies by model). The intake duct draws
fresh air through a vented cover. All connecting air
ducts (as well as the inner and outer covers) must be
properly sealed to ensure clean air is being used for
cooling the PVT system and also to prevent water
and other contaminants from entering the PVT area.
This is especially critical on units subjected to
frequent water forging.
CLUTCHING