APRILIA RS4 125 Guide

SERVICE STATION MANUAL
B043126
RS4 125

SERVICE STATION
MANUAL
RS4 125
THE VALUE OF SERVICE
As a result of continuous technical updates and specific mechanic training programs for Aprilia products,
only Aprilia Official Network mechanics know this vehicle fully and have the special tools necessary to
carry out maintenance and repair operations correctly.
The reliability of the vehicle also depends on its mechanical state. Checking the vehicle before riding it,
its regular maintenance and the use of Original Aprilia Spare Parts only are essential factors!
For further information contact the nearest Official Dealer and/or Service Centre, or consult the Yellow
Pages or search directly on the inset map in our Official Website:
www.aprilia.com
Only by requesting Aprilia Original Spare Parts can you be sure of purchasing products that were
developed and tested during the actual vehicle design stage. All Aprilia Original Spare Parts undergo
quality control procedures to guarantee reliability and durability.
The descriptions and illustrations given in this publication are not binding; While the basic characteristics
as described and illustrated in this booklet remain unchanged, Aprilia reserves the right, at any time and
without being required to update this publication beforehand, to make any changes to components, parts
or accessories, which it considers necessary to improve the product or which are required for
manufacturing or construction reasons.
Notallversions/modelsshowninthispublicationareavailableinallcountries.Theavailabilityofindividual
versions/models should be confirmed with the official aprilia sales network.
© Copyright 2011 Aprilia. All rights reserved. Reproduction of this publication in whole or in part is
prohibited. Aprilia - After sales service.
The Aprilia trademark is the property of Piaggio & C. S.p.A.

SERVICE STATION MANUAL
RS4 125
NOTE Provides key information to make the procedure easier to understand and carry out.
CAUTION Refers to specific procedures to carry out for preventing damages to the vehicle.
WARNING Refers to specific procedures to carry out to prevent injuries to the repairer.
Personal safety Failure to completely observe these instructions will result in serious risk of personal
injury.
Safeguarding the environment Sectionsmarkedwiththis symbol indicate the correct use of the vehicle
to prevent damaging the environment.
Vehicle intactness The incomplete or non-observance of these regulations leads to the risk of serious
damage to the vehicle and sometimes even the invalidity of the guarantee

INDEX OF TOPICS
CHARACTERISTICS CHAR
SPECIAL TOOLS S-TOOLS
MAINTENANCE MAIN
ELECTRICAL SYSTEM ELE SYS
ENGINE FROM VEHICLE ENG VE
ENGINE ENG
POWER SUPPLY P SUPP
SUSPENSIONS SUSP
CHASSIS CHAS
BRAKING SYSTEM BRAK SYS
COOLING SYSTEM COOL SYS
BODYWORK BODYW
PRE-DELIVERY PRE DE

INDEX OF TOPICS
CHARACTERISTICS CHAR

Rules
Safety rules
Carbon monoxide
If you need to keep the engine running while working on the vehicle, please ensure that you do so in
an open or very well ventilated area. Never run the engine in an enclosed area. If you do work in an
enclosed area, make sure to use a fume extraction system.
CAUTION
EXHAUSTEMISSIONSCONTAINCARBONMONOXIDE,APOISONOUSGASWHICHCANCAUSE
LOSS OF CONSCIOUSNESS AND EVEN DEATH.
Fuel
CAUTION
THE FUEL USED TO POWER INTERNAL COMBUSTION ENGINES IS HIGHLY FLAMMABLE AND
MAY BE EXPLOSIVE UNDER CERTAIN CONDITIONS. IT IS THEREFORE RECOMMENDED TO
CARRY OUT REFUELLING AND MAINTENANCE PROCEDURES IN A VENTILATED AREA WITH
THE ENGINE SWITCHED OFF. DO NOT SMOKE DURING REFUELLING AND NEAR FUEL VA-
POURS, AVOIDING ANY CONTACT WITH NAKED FLAMES, SPARKS OR OTHER SOURCES
WHICH MAY CAUSE THEM TO IGNITE OR EXPLODE.
DO NOT DISPERSE FUEL IN THE ENVIRONMENT.
KEEP OUT OF THE REACH OF CHILDREN
Hot components
The engine and the exhaust system components become very hot and remain hot for some time after
the engine has been switched off. When handling these components, wear insulating gloves or wait
until the engine and the exhaust system have cooled down.
Coolant
The coolant contains ethylene glycol which, under certain conditions, can become flammable.
When it burns, ethylene glycol produces an invisible flame which however can cause burns.
CAUTION
TAKE CARE NOT TO POUR COOLANT ONTO HOT ENGINE OR EXHAUST SYSTEM COMPO-
NENTS; THE FLUID MAY CATCH FIRE AND BURN WITH INVISIBLE FLAMES. WHEN CARRYING
OUT MAINTENANCE OPERATIONS, IT IS ADVISABLE TO WEAR LATEX GLOVES. EVEN
THOUGH IT IS TOXIC, COOLANT HAS A SWEET FLAVOUR WHICH MAKES IT VERY ATTRAC-
TIVE TO ANIMALS. NEVER LEAVE THE COOLANT IN OPEN CONTAINERS IN AREAS ACCES-
SIBLE TO ANIMALS AS THEY MAY DRINK IT.
Characteristics RS4 125
CHAR - 6

KEEP OUT OF THE REACH OF CHILDREN
DO NOT REMOVE THE RADIATOR CAP WHEN THE ENGINE IS STILL HOT. THE COOLANT IS
UNDER PRESSURE AND MAY CAUSE BURNS.
Used engine oil and transmission oil
CAUTION
IT IS ADVISABLE TO WEAR PROTECTIVE IMPERMEABLE GLOVES WHEN SERVICING THE VE-
HICLE.
THE ENGINE OR GEARBOX OIL MAY CAUSE SERIOUS INJURIES TO THE SKIN IF HANDLED
FOR PROLONGED PERIODS OF TIME AND ON A REGULAR BASIS.
WASH YOUR HANDS CAREFULLY AFTER HANDLING OIL.
HAND THE OIL OVER TO OR HAVE IT COLLECTED BY THE NEAREST USED OIL RECYCLING
COMPANY OR THE SUPPLIER.
DO NOT DISPOSE OF OIL IN THE ENVIRONMENT
KEEP OUT OF THE REACH OF CHILDREN
Brake and clutch fluid
BRAKE AND CLUTCH FLUIDS CAN DAMAGE THE PLASTIC OR RUBBER PAINTED SURFACES.
WHEN SERVICING THE BRAKING SYSTEM OR THE CLUTCH SYSTEM, PROTECT THESE COM-
PONENTS WITH A CLEAN CLOTH. ALWAYS WEAR PROTECTIVE GOGGLES WHEN SERVICING
THESE SYSTEMS. BRAKE AND CLUTCH FLUIDS ARE EXTREMELY HARMFUL FOR YOUR
EYES. IN THE EVENT OF ACCIDENTAL CONTACT WITH THE EYES, RINSE THEM IMMEDIATELY
WITH ABUNDANT COLD, CLEAN WATER AND SEEK MEDICAL ADVICE.
KEEP OUT OF THE REACH OF CHILDREN
Battery electrolyte and hydrogen gas
CAUTION
THE BATTERY ELECTROLYTE IS TOXIC, CORROSIVE AND AS IT CONTAINS SULPHURIC ACID,
IT CAN CAUSE BURNS WHEN IN CONTACT WITH THE SKIN. WHEN HANDLING BATTERY
ELECTROLYTE, WEAR TIGHT-FITTING GLOVES AND PROTECTIVE APPAREL. IN THE EVENT
OF SKIN CONTACT WITH THE ELECTROLYTIC FLUID, RINSE WELL WITH PLENTY OF CLEAN
WATER. IT IS PARTICULARLY IMPORTANT TO PROTECT YOUR EYES BECAUSE EVEN TINY
AMOUNTSOFBATTERYACIDMAYCAUSE BLINDNESS. IF THEFLUIDGETSINCONTACTWITH
YOUR EYES, WASH WITH ABUNDANT WATER FOR FIFTEEN MINUTES AND CONSULT AN EYE
SPECIALIST IMMEDIATELY. THE BATTERY RELEASES EXPLOSIVE GASES; KEEP IT AWAY
FROM FLAMES, SPARKS, CIGARETTES OR ANY OTHER HEAT SOURCES. ENSURE ADE-
QUATE VENTILATION WHEN SERVICING OR RECHARGING THE BATTERY.
KEEP OUT OF THE REACH OF CHILDREN
BATTERY LIQUID IS CORROSIVE. DO NOT POUR IT OR SPILL IT, PARTICULARLY ON PLASTIC
COMPONENTS. ENSURE THAT THE ELECTROLYTIC ACID IS COMPATIBLE WITH THE BAT-
TERY TO BE ACTIVATED.
Maintenance rules
GENERAL PRECAUTIONS AND INFORMATION
When repairing, dismantling and reassembling the vehicle, follow the recommendations given below
carefully.
RS4 125 Characteristics
CHAR - 7

BEFORE DISASSEMBLING COMPONENTS
•Beforedismantling components, remove dirt, mud, dust and foreign bodies from the vehicle.
Use the special tools designed for this bike, as required.
COMPONENTS REMOVAL
•Donotloosenand/or tighten screws and nuts using pliers or any other tools than the specific
wrench.
•Mark positions on all connection joints (pipes, cables etc.) before separating them, and
identify them with distinctive symbols.
•Each component needs to be clearly marked to enable identification during reassembly.
•Clean and wash the dismantled components carefully using a low-flammability detergent.
•Keep mated parts together since they have "adjusted" to each other due to normal wear.
•Some components must be used together or replaced completely.
•Keep away from heat sources.
REASSEMBLING COMPONENTS
CAUTION
BEARINGS MUST ROTATE FREELY, WITHOUT JAMMING AND/OR NOISE, OTHERWISE, THEY
NEED TO BE REPLACED.
•Only use ORIGINAL Aprilia SPARE PARTS.
•Comply with lubricant and consumables use guidelines.
•Lubricate parts (whenever possible) before reassembling them.
•Whentightening nutsand screws, starteither from thecomponents withthelargest diameter
or from the innermost components, proceeding diagonally. Tighten nuts and screws in suc-
cessive steps before applying the tightening torque.
•Always replace self-locking nuts, washers, sealing rings, circlips, O-rings (OR), cotter pins
and screws with new parts if the thread is damaged.
•When assembling the bearings, make sure to lubricate them well.
•Check that each component is assembled correctly.
•After a repair or routine maintenance, carry out pre-ride checks and test the vehicle on
private grounds or in an area with low traffic.
•Clean all mating surfaces, oil seal rims and gaskets before refitting. Smear a thin layer of
lithium-based grease on the oil seal rims. Reassemble oil seals and bearings with the brand
or batch number facing outward (visible side).
ELECTRICAL CONNECTORS
Electric connectors must be disconnected as described below; failure to comply with this procedure
causes irreparable damage to both the connector and the wiring harness:
Press the relative safety clips, if applicable.
•Grip the two connectors and disconnect them by pulling them in opposite directions.
Characteristics RS4 125
CHAR - 8

•If any signs of dirt, rust, moisture, etc. are noted, clean the inside of the connector carefully
with a jet of compressed air.
•Ensure that the cables are correctly fastened to the internal connector terminals.
•Then connect the two connectors, ensuring that they couple correctly (if fitted with clips, you
will hear them "click" into place).
CAUTION
DO NOT DISCONNECT CONNECTORS BY PULLING THE CABLES.
NOTE
THE TWO CONNECTORS CAN ONLY BE CONNECTED IN ONE DIRECTION: CONNECT THEM
THE RIGHT WAY ROUND.
TIGHTENING TORQUES
CAUTION
REMEMBERTHATTHETIGHTENINGTORQUESFOR ALL FASTENING ELEMENTS ONWHEELS,
BRAKES, WHEEL AXLES AND ANY OTHER SUSPENSION COMPONENTS PLAY A KEY ROLE
IN ENSURING VEHICLE SAFETY AND MUST COMPLY WITH SPECIFIED VALUES. CHECK THE
TIGHTENING TORQUES OF FASTENING ELEMENTS ON A REGULAR BASIS AND ALWAYS USE
A TORQUE WRENCH TO REASSEMBLE THESE COMPONENTS. FAILURE TO COMPLY WITH
THESE RECOMMENDATIONS MAY CAUSE ONE OF THESE COMPONENTS TO LOOSEN OR
EVEN DETACH, CAUSING A WHEEL TO LOCK OR COMPROMISING VEHICLE HANDLING. THIS
MAY LEAD TO FALLS, WITH THE RISK OF SERIOUS INJURY OR DEATH.
Running-in
Runningtheenginein correctly is essential for ensuring engine longevity and functionality. Twisty roads
and gradients are ideal for running in the engine, brakes and suspension effectively. Vary your riding
speed during the running in period. This ensures that components operate in "loaded" conditions and
then "unloaded" conditions, allowing the engine components to cool.
CAUTION
THE FULL PERFORMANCE OF THE VEHICLE IS ONLY AVAILABLE AFTER THE SERVICE AT
THE END OF THE RUNNING IN PERIOD.
Follow the guidelines detailed below:
•Do not fully open the throttle grip abruptly at low engine speeds, either during or after the
running in period.
•During the first 100 Km (62 miles) use the brakes gently, avoiding sudden or prolonged
braking. That is to permit the adequate adjustment of the pad friction material to the brake
discs.
Vehicle identification
CAUTION
THE MODIFICATION OF THE IDENTIFICATION CODES IS A SERIOUS PUNISHABLE CRIME.
HOWEVER, THE LIMITED WARRANTY FOR NEW VEHICLES WILL BE VOID IF THE VEHICLE
IDENTIFICATION NUMBER (VIN) HAS BEEN MODIFIED OR NOT PROMPTLY DETERMINED.
RS4 125 Characteristics
CHAR - 9

Chassis number
The chassis number is stamped on the right hand
side of the headstock.
This number consists of numbers and letters, as in
the example shown below.
ZD4TW0000YSXXXXXX
KEY:
ZD4: WMI (World manufacturer identifier) code;
TW: model;
000: version variation;
0: free digit
Yyear of manufacture
S: production plant (H= Martorelles (Spain); S=
Scorzè (Italy); 4= Zongshen (China); 5= Ponte-
dera (Italy); M= Mandello del Lario (Italy)
XXXXXX: serial number (6 digits);
CHASSIS NUMBER
The chassis number is stamped on the right hand
side of the headstock.
Dimensions and mass
DIMENSIONS
Specification Desc./Quantity
Maximum length 1,953 mm (76.89 in)
Maximum width (with mirrors) 740 mm (29.13 in)
Maximum height to the windshield 1,138 mm (44.80 in)
Saddle height 837 mm (32.95 in)
Height passenger saddle 978 mm (38.50 in)
Height handlebar 840 mm (33.07 in)
Minimum ground clearance 137 mm (5.39 in)
Wheelbase 1,350 mm (53.15 in)
Kerb weight 140 kg (308.64 lb)
Weight (without fuel) 135.8 kg (299.39 lb)
Engine
ENGINE
Specification Desc./Quantity
Engine type Single cylinder 4 stroke
Engine capacity (125) 124.2 cm³ (7.58 cu.in)
Bore x Stroke (58 x 47) mm; (2.28 x 1.85) in
Compression ratio 12.6 +/- 0.5 : 1
Electric starter
Idle speed 1900 +/- 100 rpm
Clutch multiple-disk,oil-bathedclutchwithhand control on theleftside
of the handlebar.
Characteristics RS4 125
CHAR - 10