KTM 640 DUKE II 2001 User guide

OWNERS HANDBOOK
2001
BEDIENUNGSANLEITUNG
640 DUKE II
Art.Nr. 3.205.99 11/2000

ENGLISH
1
IMPORTANT
WE STRONGLY SUGGEST THAT YOU READ THIS MANUAL
CAREFULLY AND COMPLETELY BEFORE GOING ON YOUR FIRST
RIDE. IT CONTAINS A GREAT DEAL OF INFORMATION AND
ADVICE WHICH WILL HELP YOU USE AND HANDLE YOUR BIKE
PROPERLY. IN YOUR OWN INTEREST, PLEASE PAY PARTICULAR
ATTENTION TO NOTICES THAT ARE MARKED AS FOLLOWS:

WARNING

IGNORING THESE INSTRUCTIONS, CAN ENDANGER YOUR
BODY AND YOUR LIFE.
!
CAUTION
!
IGNORING THESE INSTRUCTIONS COULD CAUSE DAMAGE TO
PARTS OF YOUR MOTORCYCLE OR THAT THE MOTORCYCLE
IS NOT ROAD-SAFE ANYMORE.
Please insert the series numbers of your motorcycle in the boxes below
Cassis number
Engine number
Stamp of dealer
COMSUMER INFORMATION FOR AUSTRALIA ONLY
TAMPERING WITH NOISE CONTROL SYSTEM PROHIBITED
Owners are warned that the law may prohibit:
(a)
The removal or rendering inoperative by any person other than for purposes of maintenance, repair
or replacement, of any device or element of design incorporated into any new vehicle for the pur-
pose of noise control prior to its sale or delivery to the ultimate purchaser or while it is in use; and
(b) the use of the vehicle after such device or element of design has been removed or rendered
inoperative by any person.
KTM S
PORTMOTORCYCLE AG RESERVES THE RIGHT TO MODIFY ANY EQUIPMENT , TECHNICAL SPECIFICATIONS , COLORS ,
MATERIALS , SERVICES OFFERED AND RENDERED , AND THE LIKE SO AS TO ADAPT THEM TO LOCAL CONDITIONS WITHOUT
PREVIOUS ANNOUNCEMENT AND WITHOUT GIVING REASONS
, OR TO CANCEL ANY OF THE ABOVE ITEMS WITHOUT SUBSTI -
TUTING THEM WITH OTHERS . I T SHALL BE ACCEPTABLE TO STOP MANUFACTURING A CERTAIN MODEL WITHOUT PREVIOUS
ANNOUNCEMENT
. I N THE EVENT OF SUCH MODIFICATIONS , PLEASE ASK YOUR LOCAL KTM DEALER FOR INFORMATION .
W
E SHALL NOT BE HELD LIABLE FOR ANY PRINTING ERRORS .

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2
Introduction
We would like to congratulate you on your purchase of a KTM motorcycle. Let us also take this
opportunity to thank you for putting your trust in us; we will not let you down.
You are now owner of a sporty and modern motorcycle which you are bound to have a great time
with provided you care for it properly. Before going for a first ride on your motorbike, you should
read this Owner’s Handbook carefully, even if this takes some of your precious time, so as to
familiarize yourself with how your motorbike is to be operated and which features it offers you.
Only by doing so will you learn how you can best tune your motorcycle to your needs and how
you can avoid bodily injuries. In addition, this Owner’s Handbook contains invaluable informa-
tion about motorcycle maintenance. At the time of printing, this User's Guide corresponded to the
latest state of this model family. It is, however, possible that we may have made slight modificati-
ons in the meantime due to development in our motorcycle design.
The Owner’s Handbook is an essential part of the motorbike and should - when the bike is sold -
be handed over to the new owner.
Many motorcyclists have a good working knowledge of motorcycle mechanics; if this is true in
your case, you will be able to use this Owner’s Handbook to carry out most of the maintenance
steps yourself. If, on the other hand, you are not very familiar with motorcycles, it might be better
to have a professional KTM dealer perform those steps marked by *found in the chapter entitled
“Maintenance Work on Chassis and Engine” of this manual.
Take special care to follow the recommended run in, inspection, and maintenance
intervals. Heeding these guidelines will significantly increase the life of your motorcycle. Be sure to
have any maintenance jobs performed by an authorized KTM dealer.
Address your special requests to an authorized KTM dealer who, should the need arise, will be
supported by the KTM importer.
Please do not forget to don your helmet, eye protection, and protective clothing when going for a
ride. KTM riders are responsible riders! We wish you a lot of fun when driving !
KTM SPORTMOTORCYCLE AG
5230 MATTIGHOFEN, AUSTRIA
ALL RIGHTS RESERVED TO MAKE ALTERATIONS TO DESIGN AND MODEL.
©by KTM SPORTMOTORCYCLE AG, AUSTRIA All rights reserved
KTM Austria’s certificate of achievement for its Quality
System ISO 9001 is the beginning of an on-going total
re-engineering quality plan for a brighter tomorrow.

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3
Page
IMPORTANT NOTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
SERIAL NUMBER LOCATING . . . . . . . . . . . . . . . . . . . . . . .4
Cassis number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Engine number, engine type . . . . . . . . . . . . . . . . . . . . . .4
OPERATION INSTRUMENTS . . . . . . . . . . . . . . . . . . . . . . .4
Clutch lever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Hand decompression lever . . . . . . . . . . . . . . . . . . . . . . .4
Choke lever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Hand brake lever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Indicator lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Ignition lock, with 4 switch position . . . . . . . . . . . . . . . .6
Ignition lock with 3 switch position . . . . . . . . . . . . . . . . .6
Combination switch . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Emergency OFF button . . . . . . . . . . . . . . . . . . . . . . . . . .6
Emergency OFF switch . . . . . . . . . . . . . . . . . . . . . . . . . .7
Filler cap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Fuel tap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Shift lever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Kickstarter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Foot brake pedal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Compression damping of fork . . . . . . . . . . . . . . . . . . . . .8
Rebound damping of fork . . . . . . . . . . . . . . . . . . . . . . . .8
Compression damping of shock absorber . . . . . . . . . . . .9
Rebound damping of shock absorber . . . . . . . . . . . . . . .9
Seat lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Supporting strap for the passenger . . . . . . . . . . . . . . . . .9
DRIVING INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . .10
LUBRICATION AND MAINTENANCE SCHEDULE . . . . . . .14
MAINTENANCE WORK ON CHASSIS AND ENGINE . . . . .16
Tool kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Checking and adjusting the steering head bearing . . . . . . .16
Changing the spring preload of the shock absorber . . . . . .17
Checking the rubber ring on the shock absorber . . . . . . . .17
Lubricate rear shock absorber linkage . . . . . . . . . . . . . . . .17
Checking chain tension . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Correcting chain tension . . . . . . . . . . . . . . . . . . . . . . . . . .18
Chain wear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Chain maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Maintaining chain tension eccentrics . . . . . . . . . . . . . . . . .19
General information about KTM disc brakes . . . . . . . . . . .19
Changing the basic position of the handbrake lever . . . . . .20
Page
Checking of brake fluid level - front brake . . . . . . . . . .20
Refilling the front brake fluid reservoir . . . . . . . . . . . . .20
Checking the front brake pads . . . . . . . . . . . . . . . . . . .21
Changing the basic position of the brake pedal . . . . . . .21
Checking the rear brake fluid level . . . . . . . . . . . . . . . .21
Refilling the rear brake fluid reservoir . . . . . . . . . . . . . .21
Checking the rear brake pads . . . . . . . . . . . . . . . . . . . .22
Dismounting and mounting the front wheel . . . . . . . . .22
Dismounting and mounting the rear wheel . . . . . . . . . .22
Checking the damping rubbers in the rear wheel . . . .23
Tires, air pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Charging the battery . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Main fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Fuses for indivitual power-consuming units . . . . . . . . . .25
Opening the head light mask . . . . . . . . . . . . . . . . . . . .25
Headlight range adjustment . . . . . . . . . . . . . . . . . . . . .26
Headlight - replacing the bulbs . . . . . . . . . . . . . . . . . . .26
Parking light - replacing the bulb . . . . . . . . . . . . . . . . .26
Flasher - replacing the bulbs . . . . . . . . . . . . . . . . . . . . .26
Stop light and tail light - replacing bulb . . . . . . . . . . . . .27
Cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Checking the coolant level . . . . . . . . . . . . . . . . . . . . . .28
Adjusting the clutch cable . . . . . . . . . . . . . . . . . . . . . . .28
Checking the setting of the hand decompression cable .28
Adjusting the choke cable . . . . . . . . . . . . . . . . . . . . . . .28
Adjusting idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Draining of float chamber of the carburetor . . . . . . . . .29
Oil circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Checking engine oil level . . . . . . . . . . . . . . . . . . . . . . .30
Change of oil and fine screen filter, bleeding of the oil
system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Changing oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Changing the fine screen filter . . . . . . . . . . . . . . . . . . .31
TROUBLE SHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . .32
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
CONSERVATION FOR WINTER OPERATION . . . . . . . . . .35
STORAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Re-initation after time of storage . . . . . . . . . . . . . . . . .35
TECHNICAL SPECIFICATIONS - ENGINE . . . . . . . . . . . . . .36
TECHNICAL SPECIFICATIONS - CHASSIS . . . . . . . . . . . . .37
HEAD WORD INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
WIRING DIAGRAMM . . . . . . . . . . . . . . . . . . . . . . . .APPENDIX
CONSUMER INFORMATION FOR USA ONLY . . . . .APPENDIX
INDEX

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4
Chassis number
The frame number is stamped on the right side of the steering head tube.
Write this number into the relevant box on page 1.
Engine number, engine type
The engine number and engine type are stamped on the right hand side of
the engine below the engine sprocket. Write the number into the box on
page no 1.
SERIAL NUMBER LOCATIONS
OPERATION INSTRUMENTS
Clutch lever
The clutch lever 1is fitted on the left hand side of the handle bar. When
engine is cold, there should be a play of 1-3 mm (0.04-0.1 in) (measured at
outer edge). !
CAUTION
!
IF THERE IS NO PLAY ON THE CLUTCH LEVER, THE CLUTCH WILL START TO SLIP. THE
CLUTCH WILL THEN OVERHEAT, DESTROYING THE CLUTCH LININGS.
Hand decompression lever
The hand decompression lever 2is only used in two special cases:
a)When the engine stalled.
It is possible that the starter motor is not able to crank the engine on the
next attempt. This is due to the fact that the automatic decompressor
doesn’t work properly. If this happens, pull the manual decompression
lever and start again. Afterwards normal starting will be possible.
b) When you want to push the motorcycle.
While pushing, pull the hand decompression lever to make it easier to get
the engine going.
!
CAUTION
!
THE SETTING OF THE HAND DECOMPRESSION CABLE SHOULD BE REGULARLY CHECKED
(SEE MAINTENANCE WORK). A LACK OF PLAY IN THE HAND DECOMPRESSION LEVER CAN
RESULT IN ENGINE DAMAGE.
Choke lever
When the choke lever 3is pulled backwards, a bore is opened in the car-
buretor which enables the engine to draw in additional fuel. This produces a
„rich“ fuel/air mixture necessary for cold start. When the choke lever is
pushed forward as far as it will go, the bore will be closed again. In this
position the choke cable must have a play of approx. 2 mm.
!
CAUTION
!
IF THERE IS NO PLAY IN THE CHOKE CABLE, THE BORE OF THE COLD STARTER SYSTEM
CANNOT BE COMPLETELY CLOSED. THIS RESULTS IN HIGH FUEL CONSUMPTION, THE
ENGINE RUNS UNEVENLY WITH EXTREME WEAR OF PISTON AND CYLINDER.
1–3 mm
2
1
3

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5
Hand brake lever
The hand brake lever 1is mounted on the right side of the handlebar.The
basic position of the handbrake lever can be changed in 4 steps
(see Maintenance work on chassis and engine).

WARNING

IF THE RESISTANCE IN THE HAND BRAKE LEVER OR FOOT BRAKE PEDAL FEELS “SPONGY”
(NOT ENOUGH RESISTANCE), THIS IS AN INDICATION THAT SOMETHING IS WRONG WITH
THE BRAKE SYSTEM. DON’T RIDE YOUR MOTORCYCLE ANYMORE WITHOUT FIRST HAVING
THE BRAKE SYSTEM LOOKED OVER BY A KTM DEALER.
Speedometer
The mileage indicator Ain the speedometer 2indicates overall mileage.
The day mileage indicator Bcan be set to 0 by means of the setting wheel C.
Turn the setting wheel forward until only zeros can be seen in the display.
Tachometer
The tachometer 3shows the engine speed in revolutions per minute (rpm).
Do not push the engine into the orange zone, which begins at 8500 rpm.
!
CAUTION
!
MAXIMUM RECOMMENDED ROTATION RATE IS 8500 RPM. ROTATION RATES EXCEEDING
8500 RPM WILL SHORTEN YOUR ENGINE’S LIFE. REFER ALSO TO THE SECTION ON RUN-
NING IN YOUR MOTORCYCLE TO BE FOUND IN THE “DRIVING INSTRUCTIONS” CHAPTER.
Indicator lamps
The green indicator lamp flashes when the flasher light is working in
the same rhythm as the flasher light. Faster flashing of the flasher
control lamp indicates a defect bulb
The blue indicator lamp lights up when the high beam is on.
The green indicator lamp lights up when the neutral gear is selected
The red cooling liquid temperature warning lamp lights up as soon
as the cooling liquid has reached a temperature of approximately
110° C (230° F).
!
CAUTION
!
IF THE RED COOLING LIQUID TEMPERATURE WARNING LAMP LIGHTS UP WHILE YOU ARE
DRIVING, THE COOLING SYSTEM IS PROBABLY DEFECT. IMMEDIATELY STOP THE ENGINE
AND CHECK THE COOLING LIQUID LEVEL. PLACE A CLOTH ON THE RADIATOR CAP. OPEN
THE CAP SLOWLY, SO THE EXCESS PRESSURE IN THE COOLING SYSTEM CAN ESCAPE.
CAUTION SCALDING HAZARD! DRIVING WITH THE WARNING LAMP ON WILL
CAUSE ENGINE DAMAGE.
A
2
B
C
1
3

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6
Ignition lock with 4 switch positions
Switch positions of ignition lock 1:
Ignition off, light off (engine can't be started)
Ignition on, light off (engine can be started)
Ignition on, light on (engine can be started)
Ignition off, light off, handlebar blocked
To switch the ignition to position turn the ignition key to position
and firmly press it into the
lock. Turn the handlebar all the way to the left, then turn the ignition
key to the left.
The ignition key can be withdrawn in position and .
Ignition lock with 3 switch positions
Switch positions of ignition lock 2:
Ignition off, light off (engine can't be started)
Ignition on, light on (engine can be started)
Ignition off, light off, handlebar blocked
To switch the ignition to position turn the ignition key to position
and firmly press it into the lock. Turn the handlebar all the way to
the left, then turn the ignition key to the left.
The ignition key can be withdrawn in position and .
Combination switch
The rocker switch LIGHTS 3actuates the high beam or low beam.
= High-beam light
= Low-beam light
The indicator switch 4returns to central position after actuation.
Press flasher switch towards switch housing to switch off the flasher.
The horn is sounded with button 5.
The light signal (high beam) is actuated with button 6.
Emergency OFF button
The red emergency-OFF button 7is arranged adjacent to the
throttle grip. To turn off the engine, push the button until the engine
comes to a standstill.
Pushing of the black starter button 8actuates the E-starter.

WARNING

ALWAYS VERIFY THAT THE TRANSMISSION HAS BEEN SET TO IDLE (NEUTRAL) BEFORE
ACTUATING THE STARTER BUTTON. IF YOU START THE MOTORCYCLE WITH A GEAR
ENGAGED, THE MOTORCYCLE WILL MOVE FORWARD.
3
6
3
4
5
1
2
7
8

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7
Emergency OFF switch
The red emergency-OFF switch 1is arranged adjacent to the throttle grip.
In this position, the E-starter is operational and the engine can
be started.
In this position, the E-starter and ignition circuits are interrup-
ted. The E-starter cannot be actuated, and the engine will not
start, not even if you attempt to start it with the kickstarter.
Pushing of the black starter button 2actuates the E-starter.

WARNING

ALWAYS VERIFY THAT THE TRANSMISSION HAS BEEN SET TO IDLE (NEUTRAL) BEFORE
ACTUATING THE STARTER BUTTON. IF YOU START THE MOTORCYCLE WITH A GEAR
ENGAGED, THE MOTORCYCLE WILL MOVE FORWARD.
Filler cap
The filler cap 3can be locked and is provided with a fuel evaporation con-
trol system.
To open the cap insert the ignition key, turn it 90° counterclockwise, then
lift off the filler cap.
To close the tank insert the filler cap, turn the ignition key 90° clockwise
and take out the key.
Fuel
The LC4 engine needs premium gasoline with an octane number of 95 or
higher. !
CAUTION
!
USE ONLY UNLEADED PREMIUM GRADE GASOLINE (95 OCTANES). NEVER USE ANY
GASOLINE HAVING LESS THAN 95 OCTANES BECAUSE IT MAY DAMAGE THE ENGINE.

WARNING

GASOLINE IS HIGHLY FLAMMABLE AND POISONOUS. EXTREME CAUTION SHOULD BE USED
WHEN HANDLING GASOLINE. DO NOT REFUEL THE MOTORCYCLE NEAR OPEN FLAMES OR
BURNING CIGARETTES. ALWAYS SWITCH OFF THE ENGINE BEFORE REFUELLING. BE
CAREFUL NOT TO SPILL GASOLINE ON THE ENGINE OR EXHAUST PIPE WHILE THE ENGINE IS
HOT. WIPE UP SPILLS PROMPTLY. IF GASOLINE IS SWALLOWED OR SPLASHED IN THE EYES,
SEEK A DOCTOR’S ADVICE IMMEDIATELY.
Fuel expands when its temperature rises. Therefore do not fill the tank to
the top (see fig.).
Fuel tap
OFF In this position the fuel tap is closed. No fuel may flow to the
carburetor.
ON When using the motorcycle, the twist grip must be set to the ON
position. Now fuel may flow to carburetor. In this position the tank
empties down to the fuel reserve of approx. 2.5 liters.
RES The reserve, approximately 2.5 liters, cannot be tapped until the twist
grip is turned to the RES position. Fill the tank as soon as possible and
remember to turn the twist grip back to the ON position so that you
will have backup fuel next time, too.
!
CAUTION
!
THE FUEL TAP SHOULD BE LOCKED WHENEVER THE MOTORCYCLE IS PARKED. IF THE TAP
IS NOT CLOSED THE CARBURETOR MAY OVERFLOW AND FUEL CAN GET INTO THE ENGINE.
35 mm
N
O
O
F
F
R
E
S
F
U
E
L
N
O
O
F
F
R
E
S
F
U
E
L
N
O
O
F
F
R
E
S
F
U
E
L
OFF ON RES
1
2
3

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8
Shift lever
The shift lever is mounted on the left side of the engine. The position of the
gears is shown in the illustration. Neutral, or the idle speed, is located bet-
ween first and second gear.
Kickstarter
The kickstarter is mounted on the left side of the engine. Its upper part can
be swivelled.

WARNING

–IF YOU WANT TO START THE ENGINE, MAKE SURE THAT YOU ALWAYS PUT ON STURDY
MOTORCYCLE BOOTS IN ORDER TO AVOID INJURIES. YOU MIGHT SLIP OFF THE KICK-
STARTER, OR THE ENGINE MAY KICK BACK AND PROPEL YOUR FOOT UPWARD WITH
GREAT VEHEMENCE.
–A
LWAYS KICK KICKSTARTER BRISKLY ALL THE WAY WITHOUT OPENING THE THROTTLE.
KICKING THE KICKSTARTER WITH NOT ENOUGH MOMENTUM, AND AN OPENED
THROTTLE GRIP INCREASE THE KICK-BACK HAZARD.
Foot brake pedal
The foot brake pedal is located in front of the right footrest. The basic posi-
tion can be adjusted to the seat position (see maintenance work).

WARNING

IF THE RESISTANCE IN THE HAND BRAKE LEVER OR FOOT BRAKE PEDAL FEELS “SPONGY”
(NOT ENOUGH RESISTANCE), THIS IS AN INDICATION THAT SOMETHING IS WRONG WITH
THE BRAKE SYSTEM. DON’T RIDE YOUR MOTORCYCLE ANYMORE WITHOUT FIRST HAVING
THE BRAKE SYSTEM LOOKED OVER BY A KTM DEALER.
Compression damping of fork
Hydraulic compression damping determines the reaction when the fork is
compressed. The degree of compression can be adjusted with adjusting
screws at the bottom of the fork legs.
The damping rate of the compression damping mechanism can be readju-
sted at the adjusting screws 1located at the fork leg. Turn it clockwise to
increase damping, and counterclockwise to reduce damping during com-
pression.
STANDARD ADJUSTMENT
– turn adjusting screw clockwise as far as it will go
– turn it back by as many clicks as are specified for the relevant type of
fork
WP Roma. . . . . . . . . . . . . . 14 clicks
Rebound damping of fork
Hydraulic rebound damping determines the reaction when the fork is
rebound. By turning the adjusting screw 2(REB), the degree of damping of
the rebound can be adjusted. Turn the knob clockwise to increase damping,
turn it counterclockwise to reduce damping during rebounding.
STANDARD ADJUSTMENT
– turn adjusting screw clockwise as far as it will go
– turn it back by as many clicks as are specified for the relevant type of
fork
WP Roma. . . . . . . . . . . . . . 16 clicks
1
1
2
2
2,3,4,5
1
N