Marzocchi MXR Air User manual

MXR
Air
INSTRUCTIONS
GENERAL RULES
1. Where specified, assemble and disas-
semble the shock absorption system us-
ing the M ARZOCCHI special tools only.
2. On reassembling the suspension system,
always use new seals.
3. Clean all metal parts with a special,
preferably biodegradable solvent, such
as trichloroethane or trichloroethylene.
4. Before reassembling, lubricate all parts
in contact with each other using silicone
fat spray or a specific oil for seals.
5. Always grease the lip seal rings before
reassembling.
6. Use wrenches with metric size only.
Wrenches with inch size might damage
the fastening devices even when their
size is similar to that of the wrenches in
metric size.

MXR
Air
FAILURES, CAUSES AND REMEDIES
This paragraph reports some failures that may occur when using the fork. It also indicates possible causes and suggests a remedy. Always
refer to this table before doing any repair work.
FAILURES CAUSES REMEDIES
Oil leaking through the bottom of slider O-rings at pumping element bottom and
adjusting rod damaged.
Replace the O-rings
Oil leaking through the top of the slider 1. Oil seal is worn out
2. Stanchion tube is scored
3. Excessive dirt on slider oil seal
1. Replace oil seal
2. Replace crown/stanchions assembly, oil
seals and dust seals
3. Clean the oil seal seat and replace oil seal
Fork has not been used for some time
and is locked out
Oil seals and dust seals tend to stick to
stanchions
Raise dust seal and lubricate stanchion
tube, dust seal and oil seal
Pressure drop Cap valve damaged Replace cap and/or valve
The fork reaches its end of stroke easily Valve at the bottom of the stanchion
damaged
Change
Excessive play of stanchions in the sliders Pilot bushings worn out Replace bushings
Fork rebounds too fast in any adjuster
position
Dirt inside fork legs Clean carefully and change oil
Adjuster position does not affect fork
operation
1. Dirt inside legs
2. O-ring into pumping element damaged
1. Clean carefully and change oil
2. Replace O-ring

MXR
Air
RECOMMENDATIONS FOR
MAINTENANCE
M ARZOCCHI forks are based on advanced
technology, supported by year-long experi-
ence in the field of professional mountain
biking. In order to achieve best results, we
recommend to check and clean the area
below the dust seal and the stanchion tube
after each use and lubricate with silicone
oil.
In general, M ARZOCCHI forks can offer top
performance from the start. However, in
some cases a short running-in period is
required (5-10 hours) for inner adjustments.
This running-in period will make fork life
longer and ensure fork top performance
over time.
IMPORTANT: change oil at least every
100 working hours and check pressure at
least every 10 working hours.
Polished forks should be cleaned with
bodywork polish at regular intervals in
order to preserve their original finish.
INSTALLATION
Installing the fork on a bicycle is a very
delicate operation that should be carried
out with extreme care. The installation should
always be checked by one of our Technical
Service Centers.
WARNING: Steer tube/headset
mounting and adjustment must be
carried out in compliance with the headset
manufacturer’s instructions. Improper in-
stallation may jeopardize the safety of the
rider.
To replace it, contact one of our Technical
Service Centers with the required tools.
WARNING: In case of improper
installation of the steer tube into the
crown, the rider might lose control of his/
her bicycle, thus jeopardizing his/her safety.
DISC BRAKE SYSTEM ASSEMBLY
WARNING: if a disc brake system
is installed, brake supports fixing
pins for cantilever or linear pull brakes can
be replaced with screws (part no.
532979QF) available as spare parts.
Tighten the above screws to 10 Nm.
Assembling the brake caliper onto the slider
is a very delicate operation that should be
carried out with extreme care.
Improper assembly might overstress the
caliper supports which might break.
When installing the disc brake system, be
sure to properly follow the instructions given
by the manufacturer.

MXR
Air
2
C
5
D
ADJUSTMENTS
FORK LEG PRESSURIZATION
Blow pressurized air through the valves (5)
on the stanchion caps to set COMPRES-
SION damping. To change the pressure
value, remove the protection cap (2) and
depressurize each leg. Fully tighten the
pump connection (C) on cap valve (5) or
pressurize until the required value is reached.
Unscrew the connection and refit the cap
(2). This adjustment is essential in order to
have the right fork response for the rider’s
weight and riding style.
The fork is pre-loaded at the factory to a
standard value of 3 bar.
REBOUND ADJUSTMENT
Each fork leg is equipped with an adjuster
screw (D) for REBOUND damping at slider
bottom.
To adjust, always start from the minimum
damping setting, i.e. with the screw fully
turned counterclockwise. Each adjusting
position can be identified by a click.
IMPORTANT: do not force the adjuster
knob (D) over its limit.

MXR
Air
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DISASSEMBLY
GENERAL
– The reference numbers given in this section relate to the components shown in the fork exploded view.
– Before starting any operation. please read the diagram below. It shows the quickest procedure and the exact disassembling sequence.
Locate the part you need to remove in the diagram, then look at the arrows to determine which other parts you need to remove first.
DISASSEMBLY DIAGRAM
CROWN AND STANCHIONS
ASSEMBLY CHANGE
FOOT BUFFER FIG. 11
PUMPING ROD FIG. 12
STOP RING. 7
FORK OIL CHANGE
PUMPING ELEMENT INNER O-RING
FIG. 13
STOP RING FIG. 14
VALVE ASSEMBLY FIG. 14
DUST SEAL FIG. 6
STANCHION TUBE CAP FIG. 1
REBOUND SPRING FIG. 12
BOTTOM ADJUSTER FIG. 3
VALVE ASSEMBLY CHANGE
FOOT NUT FIG. 4
CROWN AND STANCHIONS
ASSEMBLY FIG. 5
PUMPING ROD CHANGE
OIL SEAL FIG. 8
UPPER WASHER FIG. 9
PILOT BUSHING FIG. 10

MXR
Air
5
6
28
111
FIG. 1
Depressurize each fork leg (see section
ADJUSTMENT).
Unscrew the caps (5) with a 21 mm socket
wrench.
Remove the caps complete with O-ring (6)
from the stanchions.
FIG. 2
Push the stanchions (1) into the sliders (11)
and let all the oil drain out from the fork legs.
Pump the stanchions several times to help
oil drain off.
WARNING: Remember to always
recycle any used oil.
To change the fork leg oil follow the proce-
dure as described in section “REASSEMBLY”
from Fig. 27 to Fig. 29.
PILOT BUSHING AND SEAL
ASSEMBLY CHANGE
FIG. 3 (only left leg)
Turn fork legs upside down and press
adjuster retainer (28) with a small screw-
driver to release it.
Remove adjuster assembly (28) from the
left slider.

MXR
Air
26 7
Sx.
Dx.
1
11
19
FIG. 4
Remove foot nuts (26) and (7) by the use
of a 15 mm socket wrench.
FIG. 5
Withdraw the crown and stanchions as-
sembly (1) from the sliders (11).
FIG. 6
Remove the dust seal (19) from the top of
the sliders using a small screwdriver.

MXR
Air
20
21
A
22
FIG. 7
Remove the stop ring (20) from the sliders
by placing the screwdriver bit in one of the
three openings on the stop ring.
IMPORTANT: when removing the stop
ring, make sure not to damage its seat.
FIG. 8
Fit the slider protector (A) onto the slider
and remove the oil seal (21) with the help
of a large screwdriver.
IMPORTANT: when removing the oil seal,
make sure not to damage its seat. Once
removed the oil seals should not be used
again.
FIG. 9
Remove the upper washer (22) from the
slider.

MXR
Air
23
1825 14
3225 12
Dx.
Sx.
FIG. 10
Fit the bit of a small screwdriver into upper
edge slot of the pilot bushing (23) and lift
gently. Pull the bushing out of the slider and
make all necessary changes.
REPLACING PUMPING ELEMENT
SEALS
FIG. 11
Remove the foot buffers (18)and (32)
complete with ring (25) from the pumping
rod ends (14) and (12).
13
15
12 14
FIG. 12
Withdraw the pumping elements (14) and
(12) and the rebound spring (15) from the
stanchion tube top. Replace the seal ring
(13) if damaged or worn out (fitted to LH
pumping rod only).

MXR
Air
17
1634 3033
3
14
A
4
VALVE ASSEMBLY CHANGE
FIG. 14 (only left leg)
To check that the valve assembly is operat-
ing correctly, it is necessary to work on the
inside of the stanchion tube.
Slip off the stop ring (17) using pointed
pliers.
Pull the valve assembly out of the tube with
one finger in the same sequence as in the
figure: covering (33), valve (34) rebound
spring (30) and washer (16).
FIG. 13 (only left leg)
Remove the stop ring (4) from pumping
element bottom (14) with a small flat screw-
driver.
Mark stop ring seat into inner rod for proper
fitting.
Use the same screwdriver to remove the
ring (A) and screw inner rod until adjuster
threaded end is disengaged from pumping
element.
Remove inner rod and replace O-ring (3) if
damaged.

MXR
Air
23
22
21
B
REASSEMBLY
CAUTION: before reassembling, all metal
components should be washed carefully
with inflammable, preferably biodegrad-
able, solvent and dried with compressed
air.
PILOT BUSHING AND SEAL
ASSEMBLY
FIG. 15
Check that no dirt or debris is between
slider and bushing. Insert the pilot bushing
(23) into place so that it adheres to the
slider.
FIG. 16
Fit the upper washer (22) into the slider so
that it touches the pilot bushing.
FIG. 17
Lubricate the oil seal (21) and place it onto
the seal press (B) with the hollow side
toward the slider.
Press the oil seal until it touches the lower
washer by using the above seal press.

MXR
Air
20
19
4
14
A
3
FIG. 18
Insert the stop ring (20) into the slider
making sure it is properly seated into place.
Use buffer (B) to properly seat the ring into
the slider.
FIG. 19
Lubricate the dust seals (19) and fit them
into the stanchions from the spring end.
PUMPING ROD ASSEMBLY
FIG. 20 (only left leg)
Lubricate the O-ring (3) and fit inner rod
threaded end into pumping element (14).
Turn inner rod clockwise so that threaded
end can be seen the into pumping element
and stop ring seat (4), marked during
disassembly.
Fit stop ring (4) into inner rod seat and ring
(A) into pumping element seat.

MXR
Air
14
16
30
34
33
15
13
25
18 14
24
25
32 12
24
Sx.
Dx.
17
E
VALVE AND PUMPING ROD
ASSEMBLY (only left leg)
FIG. 21
After having overhauled or replaced the
valve unit and after having cleaned the
inside of the tube, reassemble. Assemble
valve components in correct sequence:
washer (16), rebound spring (30), valve
(34) and covering (33).
Then fit pumping rod (14) with seal ring
(13) and rebound spring (15) into the
valve assembly.
FIG. 22
Lubricate the O-rings (24) and (25) and
reassemble the foot buffers (18) and (32)
onto pumping element ends (14) and (12).
FIG. 23 (only left leg)
Fit this LH assembly into the stanchion tube
and properly seat the valve assembly (E).
Insert the stop ring (17).

MXR
Air
15
12
1
19 19
Nm11
26 7
Sx.
Dx.
FIG. 24 (only right leg)
Fit pumping element (12) and rebound
spring (15) from the stanchion tube top.
CROWN AND STANCHIONS
ASSEMBLY
FIG. 25
Fit the crown and stanchions assembly (1)
- with the dust seals in place - gently into the
sliders seals.
WARNING: to avoid any damages
to sealing surfaces, keep the stan-
chions duly lubricated and squared into the
sliders.
Press the crown and stanchions assembly
fully down and check that threaded ends of
pumping elements (14) and (12) are com-
ing out through the bottom of the sliders.
Check to see that the stanchions slide unre-
stricted by cycling the fork up and down
several times.
The tube should slide freely inside the seal
assembly without any side play. In the event
it is too hard or too soft, repeat the previous
steps described above and check compo-
nents to ensure they are not damaged.
Seat the dust seals (19) on top of the
sliders.
FIG. 26
Screw the foot nuts (26) and (7) on the
threaded elements of pumping elements
(14) and (12).
Tighten to 11 Nm.
Check to verify that the stanchions slide
properly through the stroke by pumping
them up and down several times.

MXR
Air
28
D
E
H
Travel (mm) H (mm)
80 40
100 45 Rh.
50 Lh.
5
6
1
FIG. 27
Fit the retainer (D) into the slider (E) to
reassemly the adjuster unit (28).
HOW TO FILL WITH OIL
FIG. 28
Pour oil little by little when the stanchions
are fully down and then pump with the
crown so as to have a better filling.
Check that the oil level (H) is as required in
both legs.
FIG. 29
Lubricate the O-ring (6) on the cap (5).
Lift the crown (1) and fit start caps (5) onto
stanchion threads by hand.

MXR
Air
Nm20
5
FIG. 30
Tighten the caps (5) to 20 Nm.
Pressurize as shown in section ADJUST-
ING.