APRILIA RX 50 - 2002 User manual

1
ONLY FOR THE CATALYTIC VERSION
USE ONLY UNLEADED PETROL IN CONFORMITY WITH THE DIN 51607 STANDARD, MIN. O.N. 95
(N.O.R.M.) AND 85 (N.O.M.M.) AND HIGH PERFORMANCE SYNTHETIC OIL FOR 2 STROKE ENGINES.
THE USE OF FUELS AND LUBRICANTS DIFFERENT FROM THOSE INDICATED CAUSES SEVERE
FUNCTIONAL INCONVENIENCES TO THE VEHICLE AND THE VOIDING OF THE aprilia GUARANTEE.
ONLY FOR THE CATALYTIC VERSION
To have the catalytic converter functioning correctly for long periods and to reduce possible
problems regarding the contamination of the thermal unit and of the exhaust, it is necessary to
avoid covering long distances with the engine running at constantly low rpm.
It is sufficient to alternate these periods with periods in which the engine runs at relatively high rpm,
even if only for a few seconds, but rather frequently.
What has been stated above assumes particular importance for the cold starting of the engine: in this
case, in order to reach a rpm regime sufficient to enable the “priming” of the catalytic reaction, you just
need to make sure that the temperature of the thermal unit has reached at least 50°C, which generally
occurs a few seconds after starting the engine.

2
CATALYTIC SILENCER
The catalytic version of the RX50 is fitted with a silencer with metal catalytic converter of the “platinum-
rhodium bivalent” type. This device provides for the oxidation of the CO (carbon monoxide) and of the
HC (unburned hydrocarbons) contained in the exhaust gases, changing them into carbon dioxide and
steam, respectively. Due to the catalytic reaction, the high temperature reached by the exhaust gases
results in the burning of the oil particles, thus keeping the silencer clean and eliminating the exhaust
fumes.
Avoid parking the catalytic vehicle near dry brush wood or in places easily accessible to chil-
dren, as the catalytic silencer becomes extremely hot during use; be very careful and avoid any
kind of contact before it has completely cooled down.

3
First edition: april 2002
Reprint:
Produced and printed by:
DECA s.n.c.
Via Risorgimento, 23/1 - Lugo (RA) - Italy
Tel. +39 - 0545 35235
Fax +39 - 0545 32844
E-mail: [e-mail]
www.decaweb.it
On behalf of:
aprilia s.p.a.
via G. Galilei, 1 - 30033 Noale (VE) - Italy
Tel. +39 - 041 58 29 111
Fax +39 - 041 44 10 54
www.aprilia.com
This manual contains all the main information and the
instructions required for normal use and mainte-
nance of your vehicle.
For controls and check-ups that cannot be carried out
easily with the standard equipment supplied, we ad-
vise you to consult our Dealers who can assure you
of quick and careful servicing.
To keep your aprilia vehicle always in perfect operat-
ing conditions, we advise you to insist on Original
Spares and to have repairs carried out only by aprilia
Authorized Outlets and Official Dealers.
When ordering spare parts from the Dealers, always
quote the spares code which is stamped on a sticker
placed under the saddle.
It is a good idea to make a note of the identification
code in the space provided in this manual, so that
you will always have a record of it even if the identifi-
cation sticker comes off.
All information is purely indicative and may be sub-
ject to variation without notice.

4
Carefully observe the instructions preceded by the
following warning signs:
Safety norms and regulations to protect
the driver and other people from severe
injuries or grave risks.
Caution norms and suggestions to avoid
damaging the vehicle and/or hurting
yourself or other people.
Indications to make the operations easier.
Technical information.
CONTENTS
Pag.
Technical features .................................................... 5
Identification data .....................................................8
Arrangement of the controls.....................................9
Instructions for use.................................................12
Maintenance...........................................................15
Electrical system ....................................................34
Cleaning ................................................................. 39
Long inactivity ........................................................39
Lubricant chart .......................................................41
Regular service intervals chart ..............................42
Importers................................................................44
Wiring diagram ....................................................... 50
automatic light switching version
(Automatic Switch-on Device)
catalytic version
VERSION:
Italy Holland Croatia
United
Kingdom
Switzerland Australia
Austria Denmark United States
of America
Portugal Japan Brazil
Finland Singapore South Africa
Belgium Slovenia New Zealand
Germany Israel Canada
France South Korea
Spain Malaysia
Greece Chile

5
TECHNICAL FEATURES
MOTOR
Model ..................................................................AM6
Type...................................... 2 stroke single-cylinder
with lamellar inlet
Cooling.......................... Liquid with forced circulation
Lubrication ...................................................Separate
Bore / stroke................................... 40,3 mm / 39 mm
Displacement ............................................49,75 cm3
Compression ratio............................................. 12 : 1
KICK START
To pedal (Kick-starter)
CLUTCH
Light alloy multiple disc oil bath
GEARS
Frontal clutch 6 speed unit
TRANSMISSION
Primary ........................................ Helical teeth gears
Ratio 3,55 (Z=20/71)
Secondary.........chain 1/2"x3,16" = Roller Ø7,75 mm
Ratio: 4,25 (Z=11/51)
CARBURETTOR
Model ...................................................Dell’Orto SHA
Diffuser................................................... Ø 12-14 mm
AIR FILTER
Sponge
IGNITION
Type ............................................................electronic
Spark advance reference ............................... 1,5 mm
correspondent to 20° before T.D.C.
Spark plug............................................ NGK BR9 ES
FUEL
Running-in (500 km) ......................... unleaded petrol
according to the DIN 51607 standard
min. O.N. 95 (N.O.R.M.)
and 85 (N.O.M.M.)
Aferwords:......................................... unleaded petrol
according to the DIN 51607
min. O.N. 95 (N.O.R.M.)
and 85 (N.O.M.M.)
Fuel tank capacity ............................................... 9,5 l
Reserve (with mechanical operation).................. 1,5 l
Mixer oil tank capacity......................................... 1,3 l
Reserve (with warning light on the dashboard)... 0,5 l

6
LUBRICATION
Gearbox and primary transmission .820 cm3of oil (*)
COOLING
Cooling circuit capacity ................................. 0,9 l(*)
(60% antifreeze + 40% water)
Minimum operating temperature .......................-17°C
FRAME
High-resistance one-beam structure, split over the
exhaust
REAR FORK
Made of rectangular-profile steel, mounted on anti-
friction bushings
SUSPENSIONS
Front.................................... aprilia telehydraulic fork
with reversed rods
with advanced pin, rods Ø 35
stroke 250 mm
Rear ................................ aprilia Progressive System
adjustable hydraulic mono-shock absorber
Rear wheel stroke ......................................... 260 mm
(*) see “LUBRICANT CHART”
BRAKES
Front.........................................disc brake Ø 230 mm
with hydraulic control
and floating caliper with two parallel pins
Rear .........................................disc brake Ø 220 mm
with hydraulic control
and fixed caliper
with two opposing pins Ø 28 mm
TYRES
Front.......................................................100/80 x 17"
Rear .......................................................130/70 x 17"
RIMS
Front...........................................................17 x 2,50"
Rear ...........................................................17 x 3,00"
DIMENSIONS
Max. length..................................................2060 mm
Wheelbase (slot center) ..............................1360 mm
Handlebars width ..........................................780 mm
Max. height..................................................1350 mm
Seat height....................................................865 mm
Footboard height...........................................355 mm

7
TYRE INFLATION PRESSURE
Maximum front and rear pressure: 2,5 bar
Low pressure can cause handling prob-
lems and the tendency to weave and in
extreme cases loss of control.
Moreover this will cause a great increase of roll-
ing friction.
The results are: high consumption of fuel and re-
duced maximum speed.
The disadvantage may cause a damage of the cover,
due to excessive local deformation.
Tyre pressure must be checked when the
tyres are at environment temperature,
that is, when the vehicle has not been moved in
the last 2 or 3 hours for more than 1 km.
Check the depth of the tyre tread often, if
it is worn below the allowable limit (2 -
3 mm.) change the tyre.
– The tyre should often be inspected for signs of
damage or cuts.
– Blowings or irregular wavings are showing in-
ternal damages, which request the prompt re-
placement of the tyre.
Remember: 1 mile = 1.6 km
1 km = 0.625 miles
Kind of drive Driver only
Front Rear
On mixed roads 1,8 bar 1,9 bar
On asphalt
paved roads 1,8 bar 1,9 bar

8
IDENTIFICATION DATA
It is a good rule to write down the frame and engine
numbers in the space provided in this manual.
The frame number can be used for the purchase of
spare parts.
Do not alter the identification numbers if
you do not want to incur severe penal and
administrative sanctions. In particular, the altera-
tion of the frame number results in the immediate
invalidity of the guarantee.
FRAME NUMBER (Fig. 1)
The frame number is stamped on the left side of the
steering head.
Frame n°
ENGINE NUMBER (Fig. 2)
The engine number is printed in the space provided
upper the pinion.
Engine n°
Fig. 1
Fig. 2

9
ARRANGEMENT OF THE CONTROLS
The control devices are positioned as indicated in fig-
ures 3 and 4, as follows:
Fig. 3
1) Clutch lever
2) Front brake lever
3) Twist grip
4) Rear brake pedal
5) Kick-starter
6) Gear pedal
Fig. 4
1) Turn indicator switch ()
2) Horn push button ()
3) Dimmer light switch (- ) and low beam si-
gnalling push button ()
3a) Dimmer light switch (- ) and high
beam signalling push button ()
4) Trip odometer control knob
5) Speedometer/odometer with trip counter
6) Mixer oil reserve warning light ()
7) Low beam warning light ()
7a) High beam warning light () 
8) Neutral indicator warning light ()
9) Revolution counter (rpm)
10) Turn indicator warning light ()
11) Ignition switch / steering lock / light switch
(- - - )
Remember: 1 mile = 1.6 km
1 km = 0.625 miles
Fig. 3
Fig. 4

10
IGNITION SWITCH / STEERING LOCK /
LIGHT SWITCH
The ignition switch has 4 click positions:
◆First click clockwise = ““ (start)
◆Second click clockwise = ““ (light on) (not provid-
ed in the version).
◆Central position = “” (stop)
◆Anticlockwise rotation = ““ (steering lock)
AUTOMATIC
LIGHT SWITCHING VERSION 
The vehicles provided with the Automatic Switch-on
Device can be immediately recognized, since the
lights come automatically on as soon as the engine is
started.
For this reason the light switch is replaced by a dim-
mer switch.
The lights can be switched off only by stopping the
engine.
For the versions with high beam, proceed as follows:
◆Before starting the vehicle, make sure that the
dimmer switch is in position “” (front low beam).
STEERING LOCK
Never turn the key to the "" position
while driving, in order to avoid losing
control of the vehicle.
OPERATION
To lock the steering turn the handlebars completely
to the left.
With the key on the "" position, press the key, re-
lease it and turn it to the "" position.
Remove the key.
Position Function Key removal

Steering
lock
The steering is
locked. It is neither
possible to start the
engine, nor to switch
on the lights.
It is possible to
remove the key.
Neither the engine,
nor the lights can be
switched on.
It is possible to
remove the key.
The engine can be
start.
It is neither possible
to switch the lights.
It isn't possible
to remove the
key.
The engine and the
lights can be
switched on.
It isn't possible
to remove the
key.

11
CRASH-HELMET LOCK (Fig. 5)
Using the ignition key it is possible to have access to
the crash-helmet lock positioned on the rear part of
the vehicle.
GLOVE / TOOL COMPARTMENT (Fig. 6)
It is positioned on the inner part of the left side of the
fairing.
Fig. 5
Fig. 6

12
INSTRUCTIONS FOR USE
◆Before starting the vehicle for the first time, check
that the tyres are inflated to the correct pressure
(see “TYRE INFLATION PRESSURE”) and fill the
fuel tank with premium grade petrol (see “TECH-
NICAL DATA”).
◆Fill the mixer oil tank with oil (see “LUBRICANT
CHART”).
The motor must not be filled with petrol/
oil mixed at filling stations.
◆Check the engine coolant level (see “COOLANT
CHECKING”).
◆Make sure that there are no air bubbles in the mix-
er oil pipe (from the oil tank to the pump); if neces-
sary, bleed the pump by means of the appropriate
screw (see "SEPARATE LUBRICATION”).
RUNNING
In the initial period of use is very important for the fu-
ture performance of the engine.
We advise warming up the engine before starting off,
allowing it to turn over for a few minutes at a low
speed.
If possible, drive on hill roads and/or roads with many
bends, so that the engine, the suspensions and the
brakes undergo a more effective running-in.
After the first 500 km, have the vehicle checked with
the first service coupon by an aprilia Offical Deal-
er.
If there is no oil left in the mixer oil tank,
avoid using the vehicle so as not to cause
irreparable damage to the motor.
Then bleed the system (see “SEPARATE LUBRI-
FICATION”) after filling the tank with specific oil
(see “LUBRICANT CHART).
The disc and shoes of the front brake require a run-
ning-in period (about 500 km) before reaching opti-
mum performance conditions.
Remember: 1 mile = 1.6 km
1 km = 0.625 miles.

13
STARTING (Fig. 7-8)
◆Open the fuel coock on the tank (Fig. 7).
◆Insert the ignition key and turn to “” position.
◆If the starting takes place with cold engine, push
the choke lever upwards (Fig. 8).
◆Place gears in neutral position, (neutral indicator
warning light “” comes on) or pull on clutch lever.
◆Act on the kick starter with your right foot, releas-
ing it immediately.
If the mixer oil reserve warning light ""
comes on during the normal running of
the engine, this means that the mixer oil
reserve is being used; in this case, provide for
topping up.
Do not continue to press the kickstart le-
ver or attempt to use it while the engine
is running.
Fig. 7
Fig. 8

14
◆Once you have started the engine, wait for a few
seconds, then twist the throttle, turn the accelera-
tor handle firmly as far as it will go, thus automati-
cally disconnecting the starter (a metallic click will
be heard).
◆When the engine is warm it should be started with-
out using the choke.
The engine must not remain turned on
with the battery or the voltage regulator
disconnected; this would cause irrepara-
ble damage to the electrical system.
MOVING OFF (Fig. 9)
After warming up the engine:
◆Pull in the clutch lever.
◆Engage 1st gear (gear pedal downwards).
The neutral indicator warning light “” go out.
◆Then gradually release the clutch and turn the
throttle at the same time.
CHANGING GEAR (Fig. 9)
Release the throttle, pull the clutch lever in and lift the
gear lever upwards to change to the higher gears.
Vice versa, push downwards when changing to a
lower gear.
Before riding the motor cycle we advise
you to get to know the controls and all
their functions as explained in this manu-
al. Contact your aprilia Offical Dealer if there is
anything you do not understand.
Fig. 9

15
STOPPING THE ENGINE
Release the twist grip, set the gear in neutral posi-
tion, neutral indicator warning light “” comes on,
and turn the ignition key in an ‘‘'' position.
Turn off the fuel cock (Fig. 7).
If there should be an excessive coolant
temperature during normal operation,
turn off the engine.
Wait for it to cool down, then check the level of
the coolant (see “COOLANT CHECKING”) and
top up if necessary.
If the level not is normal have the cooling system
checked by an aprilia Official Dealer.
The vehicle is equipped with a side stand
with automatic return. To prevent dama-
ges to the person and to the vehicle, put
the vehicle on its stand only after having
switched off the engine and having got off from
the vehicle l.h. side.
Open the side stand making sure it has run its en-
tire stroke; only then you may charge it with the
vehicle load.
It is absolutely forbidden to put the vehi-
cle on the stand while being seated on it.
MAINTENANCE
See “PERIODIC MAINTENANCE CHART”.
Before beginning any maintenance oper-
ation or any inspection of the vehicle,
stop the engine, extract the key, wait until
the engine and the exhaust system have cooled
down and if possible lift up the vehicle by means
of the proper equipment, on firm and flat ground.
Keep away from the red-hot parts of the engine
and of the exhaust system, in order to avoid
burns. Do not hold any mechanical piece or other
parts of the vehicle with your mouth: the compo-
nents are not edible and some of them are nox-
ious or even toxic.
If not expressly indicated otherwise, for
the reassembly of the units repeat the dis-
assembly operations in reverse order.
Usually ordinary maintenance operations can be car-
ried out by the user, but sometimes a basic knowl-
edge of mechanics and specific tools are required.
If you need assistance or technical advice consult
your aprilia Official Dealer, who can ensure you
quick and careful servicing.

16
CHECKING THE GEAR OIL LEVEL
(Fig. 10)
◆Hold the vehicle in an upright position with respect
to the ground.
◆Remove the checking screw (1) (right side cover):
the oil level is correct if it reaches the bottom edge
of the hole when the vehicle in an upright position.
◆If necessary, top up through the filler hole (2).
GEAR OIL REPLACEMENT (Fig. 10)
This operation should be carried out while the engine
is warm so that the oil drains off faster.
The procedure is as follows.
◆Unscrew the filler plug (2).
◆Place a suitably large container (min. 1000 cm3)
under the engine to catch the old oil.
◆Unscrew the drain plug (3) placed on the bottom.
◆Once all the oil has drained off, replace the drain
plug (3) and pour 820 cm3of oil into the filler hole
(2) (see “LUBRICANT CHART”).
In case of oil leakages or malfunctions,
contact your aprilia Official Dealer.
DO NOT DISPOSE OF OIL IN THE ENVI-
RONMENT.
Fig. 10

17
CLUTCH ADJUSTMENT (Fig. 11-12)
This model is equipped with two devices for adjust-
ing the length of the clutch cable.
Check the correct adjustment of the clutch cable from
time to time, ensuring that the idle stroke of the con-
trol lever is from 3 ÷ 4 mm (Fig. 11).
If this distance is not correct, turn the control lever
adjuster (1) or the adjuster on the motor cover
(Fig. 12).
If it is not possible to adjust the clutch by
means of the adjusters, contact your
aprilia Official Dealer
The clutch must be adjusted when it does not "re-
lease" correctly and the vehicle tends to move even
with the clutch pulled.
On the contrary, if the clutch “slips” the acceleration
of the vehicle will not be in proportion to the accelera-
tion of the motor.
Fig. 11
Fig. 12

18
SEPARATE LUBRICATION (Fig. 13-14)
Top up the mixer oil tank every 500 km.
The vehicle has a separate lubrication system which
includes an mixer oil tank (Fig. 13) (1,3 lwith a re-
serve of 0,5 l) and a variable-capacity oil supply
pump (the capacity varies according to the number of
revs of the motor and the opening of the throttle).
When the oil reaches reserve level, this is indicat-
ed by the coming on of the mixer oil reserve
warning light ““.
The capacity is predetermined in the design phase,
so there is no need for the user to make any adjust-
ment. It is necessary to bleed air from the pump
whenever it has to be dismantled, the mixer oil sup-
ply pipe is detached, or when the lubricant in the mix-
er oil tank is completely exhausted.
Proceed as follows:
◆Empty the fuel tank and fill it with 2 ÷ 3 lof mixture
containing 1% oil (see “LUBRICANT CHART”).
◆Start the motor and let it idle.
Fig. 13