Complete Pictorial Service Instructions for the 2002 Marathon S fork....
Remove the Schrader access cover from the
ECC knob (right fork leg from rider's perspective):
Position the ECC knob so the access port is directly above
the Schrader valve and depress the valve core to release the air from the positive chamber (shield your eyes, as some oil
may spray out with the air):
Unscrew the cap from the left fork leg (all "left" and
"right" designations in these instructions are from the rider's perspective) to gain access to the positive (outer) and negative
(center) air valves:
Relieve the air from the positive and negative air chambers,
being prepared for some oil to spray out with the air:
Use a 2mm Allen wrench to loosen the retaining screw and
remove the ECC knob from the right side:
Use a small screwdriver to remove the "C" clip from the
Remove the "Detent Pin" as pictured:
Use a small Allen wrench to remove the "detent spring."
Be sure and keep the pin and spring in a safe location, as they are very small and easily misplaced:
Use a 21mm socket wrench to loosen both top caps:
When completely unthreaded, the right top cap will slide
off of the rod:
Lift up the left top cap to expose the attached rod:
Use a thick cotton cloth or other suitable means to pad
the jaws of a pair of "channel-lock" pliers. While securing the rod, use the 21mm socket to loosen the top cap:
Unthread the top cap and separate it from the rod:
Invert the fork over a suitable receptacle to dump out
the old oil. NOTE: If your oil looks at bad as the oil pictured below, you waited too long to change your oil! While
keeping the fork inverted over the bucket, pump both rods in and out several times and extend and compress the fork to remove
as much oil as possible:
Using a 15mm socket wrench, loosen the foot nuts, one at
a time, being prepared for the respective internals to drop down:
Remove the ("negative") air-operated cartridge from the
Note the improved foot washer design--it wont fall off
of the threads like the old design:
Remove the hydraulic cartridge from the right side:
Place the hydraulic cartridge DEEP inside the oil collection bucket
and pump the rod, until there is no residual oil left in the cartridge. Wipe the assembly clean and set it aside:
Slide the lowers off of the upper assembly:
Wrap the shaft of a flat-bladed screwdriver with electrical
tape, or place a rubber pad on top of the lowers to protect them from being scratched. Insert the blade of the screwdriver
below the wiper base, and slowly pry upwards:
(NOTE: Our current recommendation is to use the Pedro's DH Tire Lever, which
has a rounded blade that provides greater force without the risk of scratching the seal head)
Take care to avoid scratching the back of the lowers with
the screwdriver as the wipers "pop" out:
Use a small screwdriver to remove the retaining rings
from the slots above the inner oil seals:
Use the flat-bladed screwdriver to remove the inner oil
seals, following the same procedure used in removing the wipers:
Remove the washers from the lowers (located just beneath the inner
If your oil is particularly dirty, you may want to remove the bushings
to facilitate cleaning the lowers. Usually, inserting the blade of a small screwdriver under the lip of the bushing
will lift it up (pictured below). If you encounter difficulty, simply use a second small screwdriver and "collapse"
the bushing inward toward the slot and then pry upwards.
Remove the bushings, clean them, and set them aside:
Yuck! Better use some biodegradable solvent to break up and wash
out that sludge. Rinse as needed.
Thoroughly dry the inside of the lowers using a clean cotton
Clean the inside and outside of the stanchion tubes. Trimming
off two opposite corners of a cotton shop towel will allow it to be rolled up and "twisted" through the inside of
the stanchion tubes:
Re-insert the bushings into the fork legs:
Replace one of the washers:
Slide a new air/oil seal onto the seal press (if
you have one). Lubricate the outside of the seal and the inside of the area where the seal
will be seated (regardless of whether you have a seal press or not). NOTE: The inner oil seals are
installed with the LETTERING FACING UP, and the GROOVED SIDE DOWN.
CLICK ON PICTURE FOR MORE INFO
If you are using a seal press, start the tapered end of the
press into the fork leg and push lightly on the press until the seal has started into the machined area of the leg. Once
the seal is properly started into the leg, increase pressure on the press until the seal is fully seated against
the metal washer.
If you do not have a seal press, start the lubed air/oil
seal into the machined area of the lower fork leg (by hand) until it is level and flush with the opening.
Use a large (about 27mm) inverted socket with an extension (or short piece of PVC pipe that fits inside
the socket) to push the seal down until it is fully seated against the metal washer:
NOTE: The seal pictured below (U-Cup) has
been replaced with our improved "air/oil" seal.
Re-install the retaining ring, being sure that it "snaps"
positively into place all the way around. REPEAT STEPS 32-35 FOR THE OTHER SIDE.
Set a short piece of PVC pipe on the floor (1-1/4" ID for 30mm forks,
1-1/2" ID for 32mm forks). Invert an Enduro Wiper and set it on top of the pipe. Generously lube the exposed area
of the wiper and the receiving area of the lowers:
Line up one leg of the lowers on top of the wiper and
gradually apply your body weight to start the leg onto the wiper, using care to start it evenly:
Increase the amount of weight applied until the wiper
seats fully against the retaining clip.
REPEAT STEPS 36-38 FOR THE OTHER SIDE
It is very important to lubricate the inside of the inner
oil seals and the wipers, as well as the outside of the stanchions before re-assemblying (PrepM and Slick Honey work well
for this, as does the Rock 'n Roll "Super Slick Grease" being used here):
Start the lowers onto the stanchion tubes one leg at a time, being
careful to slowly work each wiper lip onto its respective stanchion. Once started, slide the lowers all the way up into
the "compressed" position:
Insert the hydraulic cartridge into the right side of the fork, making
sure to center it so the threaded end goes through the hole in the bottom of the fork leg:
Insert the air-operated cartridge into the left side of the
fork, making sure to center it so the threaded end goes through the hole in the bottom of the fork leg:
Lubricate the foot nut O-rings and prepare to install them with the
15mm socket (NOTE: the socket pictured has been internally "padded" with a small piece of cloth to keep the nut from dropping
down too far into the socket):
Thread the foot nuts onto the cartridges and torque to approximately
100 Inch- Pounds:
Add 115cc of 7.5 wt Fork Fluid to the right (ECC) side. Start
with the fork extended, adding the fluid little by little, periodically compressing and re-extending the fork. Be
sure and allow the hydraulic cartridge to refill by extending and compressing the rod a few times:
Add 30cc of 7.5 wt Fork Fluid to the left side of the fork (check out
the MixMizer OIL SYRINGE):
Lubricate the O-ring at the top of the hydraulic cartridge (right side):
Line up the flat spot in the top cap center hole with the flat spot
on the hydraulic cartridge rod and push the top cap down until the C-clip slot in the rod is visible above the top cap:
Push the C-clip into place to lock the top cap to the hydraulic cartridge
rod. Start threading the top cap into the crown by hand:
Tighten the Right top cap to approximately 150 Inch-Pounds:
Carefully place the detent spring back into the hole in the top cap:
"Drop" the Detent Pin into place on top of the Detent Spring.
REMEMBER--rounded side up!
Line up the flat spot in the ECC Adjuster Knob with the flat spot
on the brass center section of the hydraulic cartridge rod and carefully press it down into place:
Turn the ECC Knob until it lines up with the Schrader valve:
Replace the Knob Securing Screw and tighten securely:
Lubricate the O-ring that seals the Left top cap to the negative air
By hand, thread the Left top cap into the air-operated cartridge
Using "channel lock" pliers with padded jaws to hold the air-operated
cartridge rod, SNUG (don't over-tighten) the top cap into the end of the rod using the 21mm socket wrench.
Lubricate the top O-ring and proceed to thread the top cap into
the crown and torque to 150 Inch-Pounds:
Add positive air to the right side Schrader valve using the proper
Marzocchi pump adapter. (Don't forget to replace the Adjuster Knob Schrader valve access cap removed in step 1)
General Positive Air Pressure Guidelines:
Rider Weight 120-155 lbs. = Air Pressure of 20-30 psi
Rider Weight 155-180 lbs. = Air Pressure of 27-37 psi
Rider Weight 180-220 lbs. = Air Pressure of 35-45 psi
Rider Weight 210-220+ lbs. = Air Pressure of 42-55 psi
Add positive air to the left side through the OFFSET Schrader valve
(refer to the air pressure guidlines in the previous step). Pressurize the Negative Air Chamber through the CENTER
NOTE: The negative air pressure setting will be considerably higher than
the positive pressure settings. A good starting point can be obtained as follows: After setting the positive pressure
in both sides, pump air into the negative chamber (center valve) until the exposed stanchion tube length just begins
to lessen. Remember to screw the protective cover removed in Step 2 back into the top cap.
Go get your fork dirty... This forks is extremely adjustable,
but will require some experimentation with the positive and negative air settings to really dial it in to your specific weight
and riding style. Be patient--it will be worth it!
Look for more model-specific pictorial instructions in the future!