CVT belts are made from different
materials in layers to withstand the
abuse during operation.
We asked a few of the top aftermarket CVT companies and hop-up
shops to give us their thoughts on
different aspects of proper CVT operations.
Dirt Wheels: What’s the proper belt
Sparks Racing: Before installing a
new belt, always clean both clutches
with compressed air and wipe the
belt contact surfaces of the clutches with a paper towel and contact
cleaner. We prefer to casually drive
a car while the belt warms up for the
first time. Belts seem to work better
and last longer when they have been
given a chance to “break in” once
installed in the car.
Dirt Wheels: Explain what the different CVT components do.
CVTech: Primary clutch spring—
The primary spring dictates the
engagement and disengagement
rpm of your clutch, ensuring that the
clutch will disengage the belt when
at idle. The primary spring is also
used to correct your shift-line rpm if it
is rising or falling.
Secondary clutch spring—The
secondary clutch spring is used to
ensure that a minimum belt tension is
maintained during operation. It can
also be used to help tune when you
are out of options in the drive clutch,
but should not be your main focus
during CVT tuning.
Clutch weights—Clutch weights
apply the proper load to the engine
and will dictate the engine rpm
during operation. A heavier weight
will load the engine and make it
operate at a lower rpm and a lighter
weight will raise the rpm.
EPI Performance offers different clutch kits to better suit your type and style of
driving. These kits consist of sand dune, mud and sport utility use, and can be
modified when adding bigger tires or more power.
Most utility ATVs have a CVT clutch when riding in rocks, and the clutch can heat
up faster than normal trail riding.
STM Powersports uses high-quality billet material for their clutches instead of cast
components. These clutches are fully rebuildable, and STM keeps all parts in stock.