" Going Fast Is Also
About Slowing Down Fast "
Innovative Kawasaki Superbike
I met Jan Greven
at a Scandinavian Open Superbike race in Anderstorp, Sweden, and he was kind
enough to let me take some photos of his very trick 163 horsepower Kawasaki Superbike.
The bike is loaded with externally visible speed tricks, but the most interesting thing was a feature that
Jan added, which links the rear
brake to the front. It was invented by a man from Switzerland.
Unlike the simple linked braking systems used on some streetbikes, this one features 2 rear
brake calipers, one above the disc and a much smaller one below it. The main purpose
is to transfer force through a system of levers to provide an ingenious advantage
The upper caliper functions as a normal rear brake, that is to stop the wheel.
But, the lower caliper isn't actually used for stopping force, (although it does
do that too.) Instead, a system of linkage "torque" arms transfers the braking torque from
the lower caliper to the swingarm and frame.
When the lower caliper grips the
disc it naturally "wants" to rotate towards the rear of the bike. This
torque force is transferred via the linkage rods, so it actually
"pulls" down on the swingarm. This makes it harder for the rear tire
to lift off the ground under hard braking ("stoppies" are cool to
watch, but you don't want them while racing !) The result is increased braking stability
as well as allowing much harder
braking ! Since the rear brake is linked to the front, it works
automatically. Wow !!!
Fast rider and also a
really good guy !!
Give his photo a
" hit " !!
Inserts on the outer part of the ram air openings reduce the size of the
openings to ... increase ram air velocity !!
This power secret is "invisible" on the dyno ... but not on the
Notice the welded aluminum gas tank and the tapered exhaust design. The
Suter dry clutch is a beautiful piece of work. This is one trick race bike
Jan has the exhaust gasses pointing into the bike's
aerodynamic wake !! This little known power secret is also invisible on
the dyno, and it's one of the subjects of my Power
News horsepower newsletter.
Note the upper caliper and the smaller lower caliper.
Behind the swingarm is the 1st linkage that connects the lower caliper's
pulling force to a triangulated lever. The pivot for the lever is mounted
in the middle of the swingarm, where the welded in section is.
From the top right of the triangulated lever, the second torque link leads to
the frame. This prevents the lever from just rotating back. Instead, it forces
the lever to transfer it's torque down onto the swingarm. Study the
photo, and you'll see how this unique set-up allows Jan to brake deep into
the corners !
Here you can see the lever and the upper linkage that leads
up to the frame. Also notice that this disc is floating, and drilled
radially in addition to the usual longitudinal drilling pattern !!
In front of the top triple clamp is an adjuster valve to
change the proportion of front and rear brake hydraulic force.