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60093400 111700

FINAL ADJUSTMENT

Open

Needle Valve

Metering Needle

More fuel

Less fuel

More fuel Less fuel

Final adjustment should be carried out only after the

running-in has been completed.

CARE AND MAINTENANCE

The minute particles of foreign matter, that are present in

any fuel may, by accumulating and partially obstructing

fuel flow, cause engine performance to become erratic

and unreliable.

O.S. 'Super-Filters' (large and small) are available, as

optional extras, to deal with this problem.

One of these filters installed to the pickup 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

carburetor.

Do not forget to clean the filters regularly to remove

dirt and lint that accumulate on the filter screens.

Also, clean the carburetor itself occasionally.

At the end of each operating session, drain out any fuel

that may remain in the fuel tank. Afterwards,energize

the glow-plug 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. Do this while the

engine is still warm.

Then, inject some after-run oil into the engine, and

rotate the engine 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-rings inside the carburetor to

deteriorate. These procedures will reduce the risks

of starting difficulties or corrosion after a period of

storage.

Dirt and dust may lodge in marked places.

Finally, when cleaning the exterior of the engine, use

methanol or a household cleaning agent. Do not use

gasoline, kerosene, or any petroleum based

chemical which can damage silicone fuel tubing.

71410150

71410200

71410250

71410300

71411200

71411250

71412300

71413550

71413600

71413700

71417100

71417200

O.S. SPEED HEX WRENCH DRIVER 1.5

O.S. SPEED HEX WRENCH DRIVER 2.0

O.S. SPEED HEX WRENCH DRIVER 2.5

O.S. SPEED HEX WRENCH DRIVER 3.0

O.S. SPEED HEX BALL WRENCH DRIVER 2.0

O.S. SPEED HEX BALL WRENCH DRIVER 2.5

O.S. SPEED FLAT HEAD SCREWDRIVER 3.0

O.S. SPEED NUT DRIVER 5.5

O.S. SPEED NUT DRIVER 6.0

O.S. SPEED NUT DRIVER 7.0

O.S. SPEED PHILLIPS SCREWDRIVER No.1

O.S. SPEED PHILLIPS SCREWDRIVER No.2

O.S. SPEED DRIVER TOOLS

Code No.

Description

71414015

71414020

71414025

71414030

71414120

71414125

71414230

71414355

71414360

71414370

O.S. SPEED HEX WRENCH TIP ONLY 1.5

O.S. SPEED HEX WRENCH TIP ONLY 2.0

O.S. SPEED HEX WRENCH TIP ONLY 2.5

O.S. SPEED HEX WRENCH TIP ONLY 3.0

O.S. SPEED HEX BALL WRENCH TIP ONLY 2.0

O.S. SPEED HEX BALL WRENCH TIP ONLY 2.5

O.S. SPEED FLAT HEAD SCREWDRIVER TIP 3.0

O.S. SPEED NUT DRIVER TIP ONLY 5.5

O.S. SPEED NUT DRIVER TIP ONLY 6.0

O.S. SPEED NUT DRIVER TIP ONLY 7.0

Code No. Description

(71520100)

(71415100)

(71415200)

(71415300)

O.S. SPEED CLUTCH WRENCH & ADJUSTER

O.S. SPEED FLYWHEEL KEY

O.S. SPEED FLYWHEEL PULLER

O.S. SPEED PLUG WRENCH

http://www.os-engines.co.jp

6-15 3-Chome Imagawa Higashisumiyoshi-ku

Osaka 546-0003, Japan

TEL. (06)6702-0225

FAX. (06)6704-2722

Dimensions (mm)

THREE VIEW DRAWING

79871020

79871055

79871180

M2.6x7

M2.6x18

M3x18

CAP SCREW SETS

(

10pcs./set

)

Code No.

Size Pcs. used in an engine

Cylinder Head Retaining Screw (4pcs.)

Cover Plate Retaining Screw (4pcs.)

Carburetor Retainer Retaining Screw (1pc.)

ENGINE EXPLODED VIEW & PARTS LIST

CARBURETOR EXPLODED VIEW & PARTS LIST

Type of screw

C...Cap Screw S...Set Screw

Type of screw

C...Cap Screw

The specifications are subject to alteration for improvement without notice.

Run the vehicle (with throttle fully open) over the

longest available straight course a few times to

observe the model’s speed. Return the vehicle to the

starting point and close the Needle-valve 10~15°and

repeat the run, taking note of the improvement in

performance.

Continue with further runs, gradually reduce the

Needle-valve setting aiming to achieve the highest

straight-line speed (optimum position).

Remember, however, if the Needle-valve is closed too

far, the engine will overheat, accompanied by visibly

diminished exhaust smoke and the model will lose

speed. At this point, throttle down immediately, stop

the vehicle and reopen the Needle-valve 30°.

After setting the Needle-valve at optimum position,

run the vehicle a few times at the straightway, and

stop the vehicle. With the engine still running, close

the throttle and allow it idle for about five seconds,

then reopen the throttle fully.

If, at this point, the engine puffs out an excessive

amount of smoke and the vehicle does not

accelerate smoothly and rapidly or even stops, it is

probable that the idle mixture is too rich. In this

case, turn the Metering needle clockwise 30~45°.

If, on the other hand, the engine tends to speed up

momentarily with little smoke and then cut out

abruptly when the throttle is opened, the idle

mixture is too lean. In this case, turn the Metering

needle counter-clockwise 30~45°.

NEEDLE VALVE ADJUSTMENT

METERING NEEDLE ADJUSTMENT

THROTTLE STOP SCREW ADJUSTMENT

If the engine runs too fast with the throttle closed, the

throttle stop screw should be turned counter-clockwise

to allow the throttle opening to be reduced.

OPTIMUM MIXTURE CONTROL POSITION

With the optimum mixture control position, light smoke

is visible during high speed running and the engine rpm

increase smoothly during acceleration. Carry out

adjustment 1.~3. patiently until the engine responds

quickly and positively to the throttle control.

Remember that, if the engine is operated with the fuel/air

mixture slightly too lean, it will overheat and run

unevenly. As with all engines, it is advisable to set both

the needle-valve and metering needle slightly on the rich

side of the best rpm setting, as a safety measure.

Finally, beyond the normal break-in period, a slight

readjustment toward a leaner needle setting may be

required to maintain maximum performance.

Note:

Please regard the standard positions in the

instruction manual as just a guide. Positions will

vary due to the fuel and silencer used. In general,

if a fuel containing less nitromenthane is used, the

needlevalve will need to be closed further.

Remember, closing the needlevalve too far can

cause rusting and damage to the engine.

CHECKING THE ENGINE

If the engine will not develop normal performance after

long time running due to wearing of parts. It is suggested

to replace necessary parts when the following symptoms

are detected.

Engine sound changes and easily overheats.

Power has dropped extremely.

Idle is unstable and/or engine tends to stop at idle.

In most cases, ball bearings, cylinder & piston assembly,

connecting rod and/or crankcase have become worn.

Check the parts carefully and replace them if necessary.

Dirt and stain stuck on the engine and silencer/manifold

cause lowering heat dissipation effect. When dirt and

stain are detected, remove the engine from the chassis

and clean it with alcohol.

REMOVING DIRT/STAIN

When storing the engine, install the cap on the exhaust

port, carburetor, etc. to prevent dust from entering the

engine.

INATALLING DUST CAPS

O.S. GENUINE PARTS & ACCESSORIES

O.S. GLOW PLUG

(71642060)

RP6

(71642070)

RP7

(71642080)

RP8

(72106850)

(72106851)

(72106870)

T-2080SC TUNED SILENCER COMPLETE SET

T-2080SC Tuned Silencer Assembly

M2001SC Exhaust Header Pipe Assembly

(72101272)

(22826140)

(72106042)

Exhaust Seal Ring (2pcs.)

Joint Spring (3pcs.)

Header Pipe Spring (2pcs.)

Exhaust Seal Ring (2pcs.)

(72414000)

(72414100)

(72414200)

Induction Silencer Filter

(3pcs.)

PRESSURE CHAMBER SET

(71550000)

INDUCTION SILENCER

ON-ROAD FILTER OIL (20ml)

(5pcs.)

(3pcs.)

(72412000)

(72412100)

(72412200)

202 Cleaner Body

202 Filter Element (4pcs.)

On-road Type

SUPER AIR CLEANER 202 ASSEMBLY

(71490000)

O.S. SPEED CARBURETOR REPAIR KIT 21

No.

Code No.

Description

Outer Head

Inner Head

Head Gasket Set (0.1mm / 0.15mm)

Built-Up Parts Set

Cylinder & Piston Assembly

Piston Pin

O.S. SPEED Piston Pin Retainer 2 (6pcs.)

Connecting Rod w/piston pin retainers (3pcs.)

Carburetor Complete (Type 21M2)

Carburetor Retainer Assembly

"O" Ring

(2pcs.)

Crankshaft Ball Bearing (Front)

Crankcase

Crankshaft Ball Bearing (Rear)

Crankshaft

Cover Gasket

Cover Plate

Glow Plug RP7

Carburetor Reducer (8.5mm Purple)

"O" Ring

Exhaust Seal Ring 21 (10pcs.)

O.S. SPEED

Flywheel Collet

(2pcs.)

O.S. SPEED

Dust Cap Set For 12-30 Class

O.S. SPEED Carburetor Repair Parts 21

(71491000)

(73301612)

(73301812)

(73300305)

(72506100)

2.5mm x 1000mm

(22826140)

(21817010)

(71801110)

O.S. SPEED CILICONE TUBE

O.S. SPEED EXHAUST SEAL RING

(2pcs.)

O.S. SPEED PISTON PIN RETAINER 4mm

(6pcs.)

O.S. SPEED FLYWHEEL COLETTE

(2pcs.)

DUST CAP SET 3mm

DUST CAP SET 16mm

(3pcs.)

DUST CAP SET 18mm

4-1

4-2

4-3

4-4

6-1

3mm

(2pcs.)/

16mm

(2pcs.)/

18mm (1pc)

Mixture Control Valve Assembly

"O" Ring (L) (2pcs.)

"O" Ring (S) (2pcs.)

Needle Assembly

"O" Ring (2pcs.)

Needle Holder Assembly

No.15 Universal Nipple Assembly

Throttle Stop Screw

"O" Ring (S) (2pcs.)

Carburetor Body

Slide Valve

Metering Needle Assembly

"O" Ring (S) (2pcs.)

Dust Cover

Ball Link No.3

Set Screw (1pc.)

Carburetor Rubber Gasket

No.

Code No.

Description

(71550001)

(71550002)

O.S. SPEED CLUTCH BEARING (1050ZZ 4pcs.)

O.S. SPEED CLUTCH BEARING (1050ZZ 10pcs.)

OUTER HEAD 8S O.S.SPEED R2101

(2A004001)

3.49 cc / 0.213 cu.in.

16.08mm / 0

633 in.

17.20mm / 0.677 in.

2.75 ps / 2.71 hp / 32,000 r.p.m.

4,000-44,000 r.p.m.

350g / 12.35 oz.

Displacement

Bore

Stroke

Output

Practical R.P.M.

Weight

(Engine)

SPECIFICATIONS

(71415400)

(71415500)

O.S. SPEED SPRING REMOVER

O.S. SPEED BODY REAMER

Crankshaft of this engine is filled with silicone.

Do not use light oil nor kerosene, etc. for

washing, or the silicone will swell. Use alcohol

or fuel for washing and dry it completely.

Note:

O.S. SPEED MAINTENANCE OIL

(71430010)

O.S. SPEED PISTON PIN RETAINER PLIERS

(71492000)

1-1

1-2

2-1

3-1

4-1

7-1

9-1

1-1

1-2

2-1

3-1

4-1

7-1

S.M3x3

9-1

31.6

UNF1/4-28

20.5

29.5

75.6

15.6

4- 3.3

2B904000

2A004100

2A004160

2B903010

2B903000

22016000

2AP17000

23755024

2B981000

23981740

24881824

23731000

2B901000

23730020

2B902000

23107100

2B907000

71642070

71533385

22615000

22826145

71801110

22884254

22082600

46066319

22781800

22082970

46066319

22082940

22082950

22848160

27881820

2B981100

22082200

2A081610

27881820

23981520

23781400

26381501

29015019

4-4

4-1

4-2

4-3

C.M2.6x18

C.M3x18

6-1

C.M2.6x7