Open Class Slipper Clutches
STM Slipper Clutches
are beautifully fabricated in anodized aluminum alloy and titanium. Selected
for use by Ducati's World Superbike team, still the best choice for higher
horsepower machines. These are the EXACT Same STM Clutches that are used
by Ben Bostrom, Noriuki Haga, Franki Chilli, and many other top road racers
world wide. STM Slipper Clutches are Now available for most Modern Sport
ALL STM Clutches are
made IN HOUSE at their Italy Shop, with the highest tolerance and quality
control. Each part is stamped with a Part number, and Serial number to
keep quality control and records of all part made. This insures what you
receive is only the best, everytime.
After years of experience
and satisfaction in the production of competition engines components,
STM Slipper Clutches use the same technology, which has been already used
on dry clutches and on wet clutches also. The result: performances get
better and component lubrication increases the efficiency of the system.
This system, working with steel balls and ramps, helps the rider while
turning to avoid the loss of rear wheel traction during hard braking.
There are obvious advantages to using slipper clutches for street applications:
they assist in avoiding dangerous skidding therefore increasing safety,
and they protect the internal parts of the engine. They also reduce rear-tire
All components come
from STM Slipper Clutch, which are made with the most sophisticated machinery.
STM selects only the best aeronautic alloys from reputable suppliers.
Drums and hubs are realized in Ergal 7075 and surface treated to last
long. Pusher plate are crafted from 7075, but it have a steel ring which
gives a stiff support to the Diaphragm Evoluzione spring. This spring
is the real heart: it is possible to chose between different kind of hardness
and adapt the clutch to rider's needs. The pusher plate kit, with the
function of checking plate opening is completed by a brassbearing rest
holder and a pusher spring hub in steel and nitride coating. This treatment
helps steel components to last longer, increasing surface hardness.
STM Slipper Clutch
kits use the original Friction Plates, Drive Plates and basket.
Designed to eliminate
rear-wheel chatter and the resulting chassis instability that occurs upon
aggressive downshifting, slipper clutches reduce engine braking to make
tap-dancing gear changers into smooth operators -- smoothness being the
key to safe, fun sport riding. In addition to better keeping the back
end under control, STM slippers offer increased clutch life, reduced clutch-lever
effort and greater sensitivity in low-traction conditions.
All STM clutches are
built to operate with minimal friction, assuring great sensitivity --
even on wet tarmac or other low-grip conditions.
is an extremely important factor. That said, superior lubrication of the
unit is guaranteed by STM's Forced Lubrication Systems. The back side
of the clutch hub has grooves in it which suck the oil in and push it
toward the discs.
Going faster in the
corners is not just about HP, it's about smoothness and Traction. It's
about the riders ability to load up the tires to their limit of grip and
keeping them there, just before the point they let go. The rider can fine
tune his suspension and chassis set up to help this situation be predictable
and accurate. What you do not want is the rear tire locking up in a high
speed corner or coming into a slow, hard braking corner. The fastest way
through a corner is smooth progressive deceleration and acceleration to
prevent any wheel hop.
A known side effect
of late braking is the chance of pushing the engine through its redline
and damaging the motor. The rev limiter only works by cutting the throttle.
It doesn't work if the rear wheel is turning the motor over at a faster
speed. This is why many newer model performance sportbikes are coming
standard with "Slipper Clutches".
The point at which
the clutch releases and the level of drag designed into the clutch is
setup to make a real difference to the way the engine braking affects
handling and the suspension set-up required as a result.
with professional race teams developing a new racebike have been quoted
saying that "The initial set-up depends on the correct adjustment
of the slipper clutch. This is most important."