Penske Racing Shocks 8900 Series - Manual (Page 14)

14
8760 Needle and Jet
The 8760 jet and needle combination have been designed to give the user a broader and more linear range of
adjustment for bleed past the piston on rebound.
The 8760 jet utilizes a spring loaded poppet valve to check the flow. This gives a better seal against the flow and a
quicker response time as the shaft changes direction.
This needle has a curved parabolic tip, which gives a very fine, linear adjustment in damping across the entire range
provided by the jet.
The 8760 needle and jet will fit any of our
adjustable shafts, but they must be used
together and cannot be interchanged with
older style needles and jets.
When installing any jet, apply a tiny drop of blue
Loctite
TM to the threads and torque to 120 in•lbs.
8900 Series Rebound Adjuster
FOR BUELL AND FLAT TRACK APPLICATIONS ONLY!!
The rebound adjuster screw on the 8900 Series shock absorber is lo-
cated in the adjustable platform at the base of the main shaft.
The rebound adjuster has 25 to 30 clicks of adjustment. Note: the external
rebound adjustment is only a fine tuning device for the main valving
located inside the shock absorber.
During the rebound (extension) stage of the shaft movement, fluid flows
through two ports in the main shaft. Inside the main shaft is a needle and
jet assembly which adjusts the amount of fluid passing through the ports.
By turning in the rebound adjuster (clockwise), the needle is moved into
the jet, restricting the flow, causing firmer rebound damping forces. In
reverse, by turning the adjuster out (counter clockwise), more oil is
allowed to pass through the ports causing lighter rebound damping
forces. This rebound adjustment assembly, is in fact a timed control for
the rebound shims located on the main piston.
The adjuster (red knob) is located at the base of the adjustable
platform. During the compression or rebound stage of the shock
movement, fluid is forced through two ports in the main shaft.
Inside the main shaft is a needle and jet assembly, which adjusts
the amount of fluid passing through the jet. By turning in the
adjuster (clockwise), the needle is forced up into the jet, restricting
the fluid, causing firmer damping forces. In reverse, by turning the
adjuster out (counter clock-wise), more oil is allowed to pass
through the jet causing lighter damping forces. The adjustment
assembly, is a timed control for the shims located on the main
piston to work.
+/ - 34 clicks*
+ = More Damping
- = Less Damping
ADJUSTER
KNOB
*