It is of vital importance, before attempting to operate your engine, to read the general 'SAFETY INSTRUCTIONS AND WARNINGS' section on pages 2-6 of this booklet and to strictly adhere to the advice contained therein. q Also, please study the entire contents of this instruction manual, so as to familiarize yourself with the controls and other features of the engine.
Keep these instructions in a safe place so that you may readily refer to them whenever necessary. It is suggested that any instructions supplied with the aircraft, radio control equipment, etc., are accessible for checking at the same time.

CONTENTS

SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE FEATURES OF FX SERIES ENGINES, BEFORE INSTALLING THE ENGINE BASIC ENGINE PARTS NEEDLE-VALVE LOCATION INSTALLATION OF THE ENGINE THROTTLE LINKAGE, SILENCER FUEL TANK LOCATION GLOWPLUG FUEL, PROPELLERS MIXTURE CONTROLS BEFORE STARTING

STARTING

2 ~~11 ~~16 ~~~~~~~41 42
RUNNING-IN (Breaking-in) IDLING ADJUSTMENT CHART MIXTURE CONTROL VALVE ADJUSTMENT, REALIGNMENT OF MIXTURE CONTROL VALVE SUBSEQUENT STARTING PROCEDURE SUBSEQUENT READJUSTMENT CARBURETOR CLEANLINESS, ENGINE CARE AND MAINTENANCE ENGINE EXPLODED VIEWS & ENGINE PARTS LISTS CARBURETOR EXPLODED VIEWS & PARTS LISTS GENUINE O.S. PARTS & ACCESSORIES ENGINE THREE VIEW DRAWINGS MEMO
SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE
Remember that your engine is not a "toy", but a highly efficient internalcombustion machine whose power is capable of harming you, or others, if it is misused. As owner, you, alone, are responsible for the safe operation of your engine, so act with discretion and care at all times. If at some future date, your O.S. engine is acquired by another person, we would respectfully request that these instructions are also passed on to its new owner. The advice which follows is grouped under two headings according to the degree of damage or danger which might arise through misuse or neglect.

WARNINGS

These cover events which might involve serious (in extreme circumstances, even fatal) injury.
These cover the many other possibilities, generally less obvious sources of danger, but which, under certain circumstances, may also cause damage or injury.
Never touch, or allow any object to come
into contact with, the rotating propeller and do not crouch over the engine when it is running.
Model engine fuel is also highly
flammable. Keep it away from open flame, excessive heat, sources of sparks, or anything else which might ignite it. Do not smoke or allow anyone else to smoke, near to it.
weakened or loose propeller may disintegrate or be thrown off and, since propeller tip speeds with powerful engines may exceed 600 feet(180 metres) per second, it will be understood that such a failure could result in serious injury, (see 'NOTES' section relating to propeller safety). allow it to come into contact with the eyes or mouth. Always store it in a clearly marked container and out of the reach of children. 3
Never operate your engine in an enclosed space. Model engines, like automobile engines, exhaust deadly carbonmonoxide. Run your engine only in an open area.
Model engines generate considerable
heat. Do not touch any part of your engine until it has cooled. Contact with the muffler (silencer), cylinder head or exhaust header pipe, in particular, may result in a serious burn.
Model engine fuel is poisonous. Do not
engine was designed for model aircraft. Do not attempt to use it for any other purpose.
If you remove the glowplug from the engine
and check its condition by connecting the battery leads to it, do not hold the plug with bare fingers.Use an appropriate tool or a folded piece of cloth.
Mount the engine in your model securely,
following the manufacturers' recommendations, using appropriate screws and locknuts. sure to use the silencer (muffler) supplied with the engine. Frequent exposure to an open exhaust may eventually impair your hearing. Such noise is also likely to cause annoyance to others over a wide area.

Install

a top-quality propeller of the diameter and pitch specified for the engine and aircraft. Locate the propeller on the shaft so that the curved face of the blades faces forward-i.e. in the direction of flight. Firmly tighten the propeller nut, using the correct size wrench.
Always check the tightness of the propeller
nut and retighten it, if necessary, before restarting the engine, particularly in the case of four-stroke-cycle engines. If a safety locknut assembly is provided with your engine, always use it. This will prevent the propeller from flying off in the event of a "backfire", even if it loosens. If you fit a spinner, make sure that it is a precision made product and that the slots for the propeller blades do not cut into the blade roots and weaken them. use an electric starter. The wearing of safety glasses is also strongly recommended.

Discard any propeller which has become
split, cracked, nicked or otherwise rendered unsafe. Never attempt to repair such a propeller: destroy it. Do not modify a propeller in any way, unless you are highly experienced in tuning propellers for specialized competition work such as pylon-racing.
Take care that the glow plug clip or battery
leads do not come into contact with the propeller. Also check the linkage to the throttle arm. A disconnected linkage could also foul the propeller.

Preferably,

After
starting the engine, carry out any needle-valve readjustments from a safe position behind the rotating propeller. Stop the engine before attempting to make other adjustments to the carburetor.
Adjust the throttle linkage so that the engine
stops when the throttle stick and trim lever on the transmitter are fully retarded. Alternatively, the engine may be stopped by cutting off the fuel supply. Never try to stop the engine physically.
care that loose clothing (ties, shirt sleeves, scarves, etc.)do not come into contact with the propeller.Do not carry loose objects (such as pencils, screwdrivers, etc.) in a shirt pocket from where they could fall through the propeller arc.
their safety, keep all onlookers (especially small children) well back (at least 20 feet or 6 meters) when preparing your model for flight. If you have to carry the model to the take-off point with the engine running, be especially cautious. Keep the propeller pointed away from you and walk well clear of spectators. Immediately after a glowplugignition engine has been run and is still warm, conditions sometimes exist whereby it is just possible for the engine to abruptly restart if the propeller is casually flipped over compression WITHOUT the glowplug battery being reconnected. Remember this if you wish to avoid the risk of a painfully rapped knuckle!

Warning!

not start your engine in an area containing loose gravel or sand. The propeller may throw such material in your face and eyes and cause injury.
FEATURES OF FX SERIES ENGINES
This range of engines is ideally suited to a variety of R/C aircraft, including trainer, sports, aerobatic and scale types. A separate precision-made needle-valve unit is installed at the rear, where manual adjustment is safely remote from the rotating propeller. With the 50SX, 61FX and 91FX, the needle-valve assembly can be installed either horizontally or vertically.

Fuel outlet Throttle Lever Cover Plate
Silicone Tube Beam Mount Fuel inlet Crankcase Drive Hub Crankshaft Propeller washer Propeller nut MAX-61FX
4. Use hexagon-head brass inlet holder (61FX) or plug screw (50SX/91FX) to blank off side boss vacated by needle- valve assembly.

50SX/91FX

Needle Extension
Needle Extension Needle-Valve Assembly

Inlet Holder

Fuel Inlet

Fuel Inlet Inlet Holder

Needle-Valve Assembly

Plug Screw (50SX/91FX)

INSTALLATION OF THE ENGINE
Installation in the model
O.S. radial motor mount A typical method of beam mounting is shown below, left. (Available as an optional extra part. See parts list) Rigid hardwood (e.g. maple)
Make sure that the mounting beams are parallel and that their top surfaces are in the same plane. CORRECT INCORRECT

Front view

Side view
Top surfaces are in the same plane.
Top surfaces Opposite are not in the same plane. beam Top surfaces are not in the same plane. Re-align the surfaces as necessary Engine does not rest firmly.

At least 15mm(5/8")

How to fasten the mounting screws.
3-4mm steel nuts Spring washer or lock washer 3-4mm steel screw Tighten second nut firmly down onto first nut. Tighten this nut first. Hardwood such as cherry or maple. O.S. radial motor mount (cast aluminum) 3.5mm steel Allen screw Spring washer

50SX 40 46FX

For 50SX, 40/46FX(Code No. 71913100) For 60FP, 61 91FX(Code No. 71905200)

61 91FX

Mounting Screw Size 50SX, 40 46FX
Steel washer Hardwood mounting beams Use mounting screws of a diameter (between 3mm and 4mm) appropriate to engine size (see table left).

3mm 4mm

THROTTLE LINKAGE
Before connecting the throttle-lever / servo linkage, make sure that no part of the linkage interferes with the internal structure of the aircraft or wiring, etc., when the throttle is fully open or fully closed. Set the throttle lever linkage so that the throttle rotor is (a) fully open when the transmitter throttle stick is fully advanced and (b) fully closed when the throttle stick is fully retarded. Adjustment of the throttle rotor opening at the idling position can then be made with the throttle trim lever on the transmitter. (Select throttle-lever and servo-horn hole positions that will avoid excessive pushrod travel causing the throttle to bind at either end.) Note: When adjusting the throttle lever angle, relative to the rotor,hold the rotor at about half-way between the open and closed positions while loosening and tightening the fixing screw, otherwise the rotor, rotor guide screw,throttle stop screw or carburettor body may become burred and damaged.

SILENCER

The exhaust outlet of the silencer can be rotated to any desired position in the following manner:

Assembly screw

E-4010 Silencer
Cone baffle Turn to requlred position

Exhaust outlet

Exhaust pressure nipple Locknut
1) Loosen the locknut and assembly screw. 2) Set the exhaust outlet at the required position by rotating the rear part of the silencer. 3) Re-tighten the assembly screw, followed by the locknut. NOTE : The standard expansion-chamber type silencer is quite effective, but reduces power to some degree.
Reminder! Model engines generate considerable heat. Do not touch any part of your engine until it has cooled. Contact with the muffler (silencer), cylinder head or exhaust header pipe, in particular, may result in a serious burn. Keep your hands and face away from exhaust gas or you will suffer a burn. 50SX 40 46FX
Suggested Fuel Tank Capacities approx 300cc 61FX 91FX approx 350cc approx 450cc

Attention to tank height

Fuel level

FUEL TANK LOCATION

Suggested fuel tank capacities are listed opposite. These will allow 12-13 minute flights. Locate the fuel tank so that the top of the tank is 510mm (1/4-3/8") above the level of the needle-valve. Be sure to use a pressurized fuel system by connecting the muffler pressure nipple to the ventpipe of the fuel tank.

GLOWPLUG

Since the glowplug and fuel combination used may have a marked effect on performance and reliability, it would be worthwhile to experiment with different plug types. Recommended O.S. plugs are Nos. 8, A5 and A3. Carefully install plug finger-tight, before final tightening with the correct size plug wrench.

Glowplug life

Particularly in the case of very high performance engines, glowplugs must be regarded as expendable However, plug life can be extended and engine performance maintained by careful use, i.e.: Install a plug suitable for the engine. Use fuel containing a moderate percentage of nitromethane unless more is essential for racing events. Do not run the engine too lean and do not leave the battery connected while adjusting the needle.

The role of the glowplug

With a glowplug engine, ignition is initiated by the application of a 1.5-volt power source. When the battery is disconnected, the heat retained within the combustion chamber remains sufficient to keep the plug filament glowing, thereby continuing to keep the engine running. Ignition timing is 'automatic' : under reduced load, allowing higher rpm, the plug becomes hotter and, appropriately, fires the fuel/air charge earlier; conversely, at reduced rpm, the plug become cooler and ignition is retarded.

When to replace the glowplug
Apart from when actually burned out, a plug may need to be replaced because it no longer delivers its best performance, such as when: Filament surface has roughened and turned white. Filament coil has become distorted. Foreign matter has adhered to filament or plug body has corroded. Engine tends to cut out when idling. Starting qualities deteriorate.
Select, by practical tests, the most suitable fuel from among the best quality fuels available in your country for model use. For the best performance, a fuel containing 5% to 20% nitromethane is preferable. Lubricants may be either castor-oil or a suitable synthetic oil ( or a blend of both ) provided that they are always of top quality. For consistent performance and long engine life, it is essential to use fuel containing AT LEAST 18% lubricant by volume. Some fuels containing coloring additives tend to deteriorate and may adversely affect running qualities. Once a satisfactory fuel has been selected and used for a while, it may be unwise to needlessly change the brand or type. In any engine, a change of fuel may cause carbon deposits in the combustion chamber or on the piston head to become detached and lodged elsewhere, with the risk of this causing unreliable operation for a while. If, however, the adoption of a different fuel is unavoidable, check the engine for the first few flights on the new fuel, by temporarily reverting to the running-in procedure.
Reminder! Model engine fuel is poisonous. Do not allow it to come into contact with the eyes or mouth. Always store it in a clearly marked container and out of the reach of children. Reminder! Model engine fuel is also highly flammable. Keep it away from open flame, excessive heat, sources of sparks, or anything else which might ignite it. Do not smoke, or allow anyone else to smoke, near to it.

PROPELLERS

Suggested propeller sizes are listed on page 15. The suitability of the prop depends on the size and weight of the model and type of flying. Determine the best size and type after the engine has been run in. Check the balance of the propeller before fitting it to the engine. Unbalanced propellers cause vibration and loss of power. Wooden propellers are to be preferred. Some nylon propellers are not strong enough to withstand the high power output of these engines and a thrown blade can be very dangerous.
50SX 40FX 116~10,126 106,10.56,116~7 10.56,116~8,126~7 126~8,136~(3-blade)

Aerobatic

MIXTURE CONTROLS
Two mixture controls are provided on these engines.
The Needle Valve (at rear of engine) When set to produce maximum power at full throttle, this establishes the basic fuel/air mixture strength. The correct mixture is then maintained by the carburetor's built-in automatic mixture control system to cover the engine's requirements at reduced throttle settings. The Mixture Control Valve (carburetor) This meters fuel flow at part-throttle and idling speeds to ensure reliable operation as the throttle is opened and closed. The Mixture Control Valve is factory set for the approximate best result. First run the engine as received and readjust the Mixture Control Screw only if necessary.

46FX 61FX

118~10,127~9

(tuned silencer used)

129~11
91FXRING 158,166~8,176 Reminder!

1311~13,1410~11

Never touch, or allow any object to come into contact with, the rotating propeller and do not crouch over the engine when it is running.

Type of Carburetor

61FX 40B 91FX

60C 60F

BEFORE STARTING
Tools, accessories, etc. The following items are necessary for operating the engine. 1 Fuel Model glowplug engine fuel of good quality, preferably containing a small percentage of nitromethane. 2 Glowplug O.S. No.8 glowplug is fitted to the engine. 3 Propeller Suggested size is 10x6(40FX), 11X6 (46FX), 12X6 (50SX, 61FX), or 15x8(91FX). 4 Glowplug battery The power source for heating the glowplug may be either a large heavy-duty 1.5volt dry cell, or preferably, a 2-volt rechargeable lead-acid cell (accumulator).
If a 2-volt cell is employed, use a resistance wire, as shown, to reduce applied voltage, otherwise element will overheat and burn out. 1.5 volt heavy-duty or 2 volt rechargeable dry battery lead-acid cell (at least 5Ah)
Warning (Very hot) Never touch the nichrome wire while the battery is connected.
Resistance coil (nichrome wire)
to ge ss. e olta er v ightn Low uce br red e Raisage to volt ease. incr htness brig

Battery leads

Adjust applied voltage by changing the position of clip on resistance coil until glowplug element is glowing bright red.
5 Battery leads Battery leads These are used to conduct current from the battery to the glowplug. Basically, two leads, with clips, are required, but, for greater convenience, twin leads with special glowplug connectors, as shown on the right, are commercially available.
6 Fuel tank For installation in the model, a 300cc (10.6oz.) for 50SX and 40,46FX, a 350cc (12oz.) for 61FX, a 450cc (15.8oz.) for 91FX tank, is suggested. 7 Fuel bottle or pump For filling the fuel tank, a simple, polyethylene "squeeze" bottle, with a suitable spout,is all that is required. Alternatively, one of the purpose-made manual or electric fuel pumps may be used to transfer fuel directly from your fuel container to the fuel tank. 8 Electric starter and starter battery An electric starter is recommended for starting.

12V Battery

10 Silicone tubing This is required for the connection between the fuel tank and engine. 11 Plug wrench Used for tightening glowplug. The O.S. long plug wrench is available as an optional accessory.

Fully opened position Set at this point
RUNNING-IN ("Breaking-in")
All internal-combustion engines benefit from extra care when they are run for the first few timesknown as running-in or breaking-in. This allows the working parts to mate together under load at operating temperature. Therefore, it is vitally important to complete the break-in before allowing the engine to run continuously at high speed and before finalizing carburetor adjustments. However, because O.S. engines are produced with the aid of the finest modern precision machinery and from the best and most suitable materials, only a short and simple running-in procedure is called for and can be carried out with the engine installed in the model. The process is as follows. 1. Install the engine with the propeller intended for your model. Open the needle-valve to the advised starting setting and start the engine. If the engine stops when the glow plug battery disconnected, open the needle-valve to the point where the engine does not stop.Run the engine for one minute with the throttle fully open, but with the needlevalve adjusted for rich, slow "four-cycle"operation. 2. Now close the needle-valve until the engine speeds up to "two-cycle"operation and allow it to run for about 10 seconds, then reopen the needlevalve to bring the engine back to "fourcycle"operation and run it for another 10 seconds. Repeat this procedure until the fuel tank is empty. 3. Re-start and adjust the needle-valve so that the engine just breaks into "two-cycle" from "fourcycle" operation, then make three or four flights, avoiding successive "nose-up" flights. 4. During subsequent flights, the needle-valve can be gradually closed to give more power. However, if the engine shows signs of running too lean, the next flight should be set rich. After a total of ten to fifteen flights, the engine should run continuously, on its optimum needle-valve setting, without loss of power as it warms up. 5. After the completion of the running-in adjust the carburetor at optimum setting referring to MIXTURE CONTROL VALVE ADJUSTMENT section and SUBSEQUENT READJUSTMENT section.

20-30 open from maximum r.p.m. setting.
Re-set the idling position at a little higher r.p.m.

Open the throttle fully.

Engine stops. Engine stops. Engine stops. Refer to the next section.
Does the engine regain full power? Yes. Continue running at high speed for 10 seconds. Close the throttle. Run at idling speed for 5 seconds.
Does the engine stop? No. Apply full throttle.
Does the engine regain full power immediately?

Yes. OK

MIXTURE CONTROL VALVE ADJUSTMENT
With the engine running, close the throttle and allow it to idle for about five seconds, then open the throttle fully. If, at this point, the engine is slow to pick up and produces an excess of exhaust smoke, the mixture is too rich. Correct this condition by turning the Mixture Control Screw clockwise 15-30. If the mixture is excessively rich, engine rpm will become unstable: opening the throttle will produce a great deal of smoke and rpm may drop suddenly or the engine may stop. This condition may also be initiated by excessively prolonged idling. If,on the other hand, the mixture is too lean, this will be indicated by a marked lack of exhaust smoke and a tendency for the engine to cut out when the throttle is opened. In this case, turn the Mixture Control Screw counter-clockwise 90to positively enrich the idle mixture, then turn the screw clockwise gradually until the engine regains full power cleanly when the throttle is reopened. Carry out adjustments patiently until the engine responds quickly and positively to the throttle control.
Note: Mixture Control Valve adjustments should be made in steps of 15-30 initially, carefully checking the effect, on throttle response, of each small adjustment.
REALIGNMENT OF MIXTURE CONTROL VALVE
In the course of making carburetor adjustments, it is just possible that the Mixture Control Valve may be inadvertently screwed in or out too far and thereby moved beyond its effective adjustment range. Its basic setting can be re-established as follows: Close the throttle rotor gradually from the fully opened position until it is just fully closed. (Do not turn further.) Then, screw in the Mixture Control Screw until it stops. Now unscrew the Mixture Control Screw as indicated below.
approx turns approx21 2turns

approxturn

SUBSEQUENT STARTING PROCEDURE
Once the optimum needle-valve setting has been established (see page 19, Needle-valve adjustment diagram) the procedure for starting may be simplified as follows. 1. Open the needle-valve one half-turn (180) from the optimum setting. 2. Set the throttle one-quarter open from the fully closed position, energize the glowplug and apply the electric starter. When the engine starts, reopen the throttle and re-adjust the needle-valve to the optimum setting. Note: When re-starting the engine on the same day, provided that atmospheric conditions have not changed significantly, it may be practicable to restart the engine on its optimum(running) setting.

SUBSEQUENT READJUSTMENT

Once the engine has been run-in and the controls properly set up, it should be unnecessary to alter the mixture settings; except to make minor adjustments to the Needle-Valve occasionally, to take account of variations in climatic conditions. The use of a different fuel, however, particularly one containing more, or less, nitromethane and/or a different type or proportion of lubricating oil, is likely to call for some readjustment of the Needle-Valve. Remember that, as a safety measure, it is advisable to increase the Needle-Valve opening by an extra half-turn counter-clockwise, prior to establishing a new setting. The same applies if the silencer type is changed. A different silencer may alter the exhaust pressure applied to the fuel feed and call for a revised NeedleValve setting. The use of a different glowplug may also require compensating carburetor readjustments.

CARBURETOR CLEANLINESS

The correct functioning of the carburetor depends on its small fuel orifices remaining clear. The minute particles of foreign matter that are present in any fuel, can easily partially obstruct these orifices and upset mixture strength so that engine performance becomes erratic and unreliable. O.S.'Super-Filters'(large and small ) are available, as optional extras, to deal with this problem. One of these filters, fitted to the outlet tube inside your refueling container, will prevent the entry of foreign material into the fuel tank. It is also recommended that a good in-line filter be installed between the tank and needle-valve. Do not forget to clean the filters regularly to remove dirt and lint that accumulate on the filter screen. Also, clean the carburetor itself occasionally.
ENGINE CARE AND MAINTENANCE
1. At the end of each operating session, drain out any fuel that may remain in the fuel tank. 2. Next, energize the glowplug and try to restart the engine to burn off any fuel that may remain inside the engine. Repeat this procedure until the engine fails to fire. Remove the glowplug and eject any residue by rotating the engine with an electric starter for 4 to 5 seconds while the engine is still warm. 3. Finally, inject some after-run oil into the engine. Rotate the engine a few times by hand, to make sure that it is free, and then with an electric starter for 4 to 5 seconds to distribute the oil to all the working parts. Note: Do not inject after-run oil into the carburetor as this may cause the O-ring inside the carburettor to deteriorate. These procedures will reduce the risk of starting difficulties and of internal corrosion after a period of storage.

EXPLODED VIEW (50SX)

C.M315

o 8 i-9 9

C.M2.618

6-1 6-0 = q w e r r-1 r-2 r-3 r-4 r-5 r-6 r-7 r-8 r-9 r-10 r-11 t

26625210

EXPLODED VIEW (91FXRING)

2 y 7 8-8-2

N.M3.56

C.M3.510

t-6 t-8 t-7 t-3 t-4 t-1 t-10 t-2 t-5 t
ENGINE PARTS LIST (91FX RING)
8-1 8-0 0-1 = q w e r t t-1 t-2 t-3 t-4 t-5 t-6 t-7 t-8 t-9 t-10 y
Description Cylinder Head Cylinder Liner Piston Ring Piston Piston Pin Piston Pin Retainers (2) Connecting Rod Carburetor (Type 60F) Carburetor Gasket Carburetor Retaining Screw (2pcs.) Propeller Lock Nut Set Drive Hub Woodruff Key Thrust Washer Crankshaft Ball Bearing (F) Crankcase Crankshaft Ball Bearing (R) Crankshaft Gasket Set Cover Plate Assembly Cover Plate Body Needle "O"Ring Set Screw Needle Valve Holder Assembly Needle Valve Holder Ratchet Spring Fuel Inlet Plug Screw Fuel Outlet Screw Set Glow Plug No.8 E-4020 Silencer Assembly Assembly Screw Retaining Screw (2pcs.) Pressure Fitting Needle Valve Extension Cable Set

72200080

1 1-11-2-1
CARBURETOR 40B (50SX,40,46FX)

1 1-2 1-2-1

CARBURETOR 60C (61FX)

N.+M3.5X6 6

N.+M3.5X9
CCap Screw FFlat Head Screw NRound Head Screw SSet Screw No.

1 1-1 1-2-8 9

Code No. 46215000 25081700

Description

Throttle Lever Assembly Throttle Lever Fixing Screw Throttle Lever Mixture Control Valve "O"Ring Carburettor Rotor Rotor Spring Carburettor Body Throttle Stop Screw (W / Spring) Fuel Inlet (W / Washer) Carburettor Gasket Carburettor Fixing Screw
Throttle Lever Assembly Throttle Lever Throttle Lever Fixing Screw Mixture Control Valve "O"Ring Carburettor Rotor Rotor Spring Carburettor Body Throttle Stop Screw (W / Spring) Fuel Inlet (W / Washer) Carburetor Gasket Carburetor Retaining Screw

N.+M36

CARBURETOR 60F (91FXRING)

3-1 3-2 3

3 3-1 3-7 8
Code No. 29015019 25081700
Throttle Lever Assembly Carburettor Rotor Mixture Control Valve Assembly "O" Ring (L) "O" Ring (S) Carburettor Body Rotor Guide Screw Fuel Inlet (W / Washer) Carburetor Gasket Carburetor Retaining Screw (2pcs.)
O.S. GENUINE PARTS & ACCESSORIES

s O.S. GLOW PLUGS

(71608001)

s SPINNER NUT

s LONG PROPELLER NUT SETS

(71605100)

5/16"-24

Type of Engine

50SX. 40. 46FX 61FX. 91FX

73101000 73101010

1/4"-28 5/16"-24

(71605300)

23024009 1/4"-28(L) 45024000

s SILENCER EXTENSION

ADAPTORS
s SILENCER EXHAUST s PROPELLER NUT SETS
ADAPTORS FOR TRUTURN SPINNERS

(73101020)

Code No. Type of EngineSilencer
26625500 50SX. 40.46FX(873) 61FX(E-4010).91FX(E-4020) Length 35mm 61FX(E-4010).91FX(E-4020)
50SX. 40.46FX(873) 61FX(E-4010). 91FX(E-4020)

For 50SX. 40.46FX

s EXHAUST

HEADER PIPE

(72101230)

s SUPER SILENCERS

s O.S. SILICONE

TUBE ASSEMBLY

s SUPER FI LTER

(72403050)

s LOCK WASHER

(10Sets)

Code No. For 61FX 91FX

873S E-4010S

50SX. 4046FX 61FX

Code No. Type of Engine

40.46FX 61FX.91FX
Code No. Size Type of Engine
M3 M4 50SX. 40.46FX 61FX.91FX

25425020 26028010

s T-4010 TUNED SILENCER

(72101120)

s LONG SOCKET WRENCH

WITH PLUG GRIP

(71521000)

s BUBBLE ELIMINATING

TANK WEIGHT

(71531000)

For 61FX

MAX-50SXRING

Dimensions(mm)
SPECIFICATIONS s Displacement 8.17 cc (0.499 cu.in.) 22.0mm (0.866 in.) s Bore 21.5mm (0.847 in.) s Stroke s Practical R.P.M. 2,000~20,000 r.p.m. 1.8 bhp / 17,000 r.p.m. s Power output 390g (13.76 oz.) s Weight

UNF1/4-28

60.7 121

THREE VIEW DRAWING

MAX - 40FX SPECIFICATIONS s Displacement 6.47 cc (0.395 cu.in.) 20.5mm (0.807 in.) s Bore 19.6mm (0.772 in.) s Stroke s Practical R.P.M. 2,000~17,000 r.p.m. 1.36 bhp / 16,000 r.p.m. s Power output 386g (13.6 oz.) s Weight
MAX - 46FX SPECIFICATIONS s Displacement 7.45 cc (0.455 cu.in.) 22.0mm (0.866 in.) s Bore 19.6mm (0.772 in.) s Stroke s Practical R.P.M. 2,500~17,000 r.p.m. 1.62 bhp / 16,000 r.p.m. s Power output 375g (13.2 oz.) s Weight

70 60.5 19.5

Dimensions(mm) 39
MAX - 61FX SPECIFICATIONS s Displacement 9.95 cc (0.607 cu.in.) 24.0mm (0.945 in.) s Bore 22.0mm (0.866 in.) s Stroke s Practical R.P.M. 2,000~17,000 r.p.m. 1.9 bhp / 16,000 r.p.m. s Power output 550g (19.42 oz.) s Weight

25 4.2

4.66.5 29.1 100.5

UNF5/16-24

MAX - 91FXRING SPECIFICATIONS s Displacement 14.95 cc (0.912 cu.in.) 27.7mm (1.091 in.) s Bore 24.8mm (0.976 in.) s Stroke s Practical R.P.M. 2,000~16,000 r.p.m. 2.8 bhp / 15,000 r.p.m. s Power output 550g (19.42 oz.) s Weight

24.7 4-4.2

UNF5/16-24 43.5

42.6 61

Dimensions(mm) 41

81.5 103

UNEQ UA
L I TY PRECISION & P QUA ERF ED OR
ISH LE EL ING THE STAN RDS OF EXC DA
C Copyright 2001 by O.S.Engines Mfg. Co., Ltd. All rights reserved. Printed in Japan.

110101

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