Vortex MINI ROK Owner's Manual

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

MINI ROK

OWNER’S

MANUAL

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

INDICE

1. GENERAL INFORMATION 3

1.1. Introduction 3

1.2. Symbols 3

1.3. Safety Information 3

1.4. Technical Specifications 4

1.5. Special Technical Specifications for Homologated Engine 4

1.6. Packaging 4

2. ENGINE ASSEMBLING 5

3. ENGINE/CHASSIS ASSEMBLY 15

4. STARTING AND BRAKE-IN 22

5. SERVICING YOUR ENGINE 23

5.1. Maintenance Schedule and Adjustments 23

5.2. Torque Chart 23

5.3. Sizes and Measures 24

5.4. Chain 24

5.5.Throttle Cable 24

5.6. Carburettor 24

5.7. Spark Plug 25

5.8. Exhaust 26

5.9. Clutch and Starter Gear 26

5.10. Pinion 28

5.11.Cylinder Head 29

5.12.Cylinder 30

5.13.Piston 31

5.14.Connecting Rod 32

5.15.Bottom End 32

6. ENGINE EXPLODED VIEW AND PARTS LIST 33

7. CONTACTS 41

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

1.1. INTRODUCTION

Thank you for your purchasing of a Vortex engine. This manual contains information on how to
help you with getting the best results from your new engine. Furthermore, it will explain you how
to operate your Vortex engine safely and in a proper manner.

Vortex update this manual constantly. All the information in this manual is based on the latest
experience and product information available at the time of writing.
Vortex reserve the right to make any kind of changes to this manual at anytime without notice and
without incurring in any obligation.

This manual shall be considered part of the Vortex engine and should remain with the engine itself
if resold.

1.2. SYMBOLS

Personal injury Mechanical Danger Caution

Pay attention to the symbols of this manual. They alert you of dangerous situations for you or for
your engine.

1.3. SAFETY INFORMATION

-Do not start the engine indoor as garages, trailers, etc. Start the engine in a well-ventilated area
only. Exhaust emissions are hazardous to your health.

-Always wear gloves and proper clothing when working on your engine.

-Use caution when handling fuel. Gasoline is flammable and explosive. When working with fuel, do
not smoke or use it near fire or flames. Avoid any skin contact and inhaling fuel vapors.

-Never touch moving parts when the engine is running.

-During operation both engine and muffler, become very hot. Do not touch them and do not place
anything on them after operation.

-Do not touch the spark plug or cable. It may provoke electrical shocks.

-Understand the operation of all controls and learn how to stop the engine quickly in case of
emergency.

-Do not use the engine without clutch cover and chain protection.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

1.4. TECHNICAL SPECIFICATIONS

Cylinder Displacement (max)

60cc.

Cylinder Bore (max)

42,10 mm.

Piston Stroke

43,00 mm.

Admission system

Piston Port

Cooling System

Free air

Carburetor

Dell’Orto PHBG 18 BS

Ignition System

Selettra

Ignition Type

Digital

Ignition Timing

3 mm.

Spark Plug Gap

0,8 mm.

Fuel Mixture

3%

Engine Weight

-All sizes and measurements in this manual are expressed in metrics.

-Always use original Vortex parts and proper tools when working on your engine.

-Proper fuel mix is necessary for optimum engine life and performance.

1.5. SPECIAL TECHNICAL SPECIFICATIONS FOR HOMOLOGATED ENGINE

Vortex Mini Rok Engine is produced in one version only. However, refer to your country
homologation file for eventual specific rules and/or sizes.

1.6. PACKAGING

Your engine will be packed in a sealed box with the Vortex logo printed on and a sticker with
model and serial number attached. It will be a second box complete with accessories as
carburettor, muffler, fuel pump, air box, etc.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

2. ENGINE ASSEMBLING

In order to perform this job, you will need the following tools:

Compressed air

Allen Wrench

3 - 4 - 5 - 6 - 8 mm

Fixed Wrench

5 - 7 - 8 - 10 – 14 - 17 mm

Flat Pliers

Socket Spanner

11 mm

Hooker

Straight Ruler

Cross Screwdriver

Flat Screwdriver

Torque Wrench

1

Compressed air

Unpack the engine and remove any packaging
material on it.

2

6mm Allen Wrench

Lay the engine on its side and attach the engine
mount to the engine base with four 8 mm Allen
screws.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

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3

Engine Wheelbase Measurements in case you
need to drill your engine mount.

4

10mm Fixed Wrench

Attach the specific metal-chromed bracket
provided to the engine by using 2 of the 4 silent
blocks provided. Pass them through the support
in the engine and tighten with washer and 6
mm nut. Sometimes thread on the silent block
could be short. Use any threadlocker then.

5

10mm Fixed Wrench

Attach 1 of the remaining 2 silent blocks to the
front end of the bracket. Tighten with washer
and 6 mm nut. Sometimes thread on the silent
block could be short. Use any threadlocker
then.

6

10mm Fixed Wrench

Insert the silent block through the upper hole
on the specific metal-chromed bracket. Then
attach the brown cable (earth) coming from the
ignition, a flat washer and 6 mm nut. Tighten
everything. Sometimes thread on the silent
block could be short. Use any threadlocker
then.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

7

3 mm Allen Wrench + 7 mm Fixed

Wrench

Insert the two 4x30 mm screws into the plastic
electric plug. Attach the electric plug to the
short bracket provided. Secure it with washer
and 4 mm nut.
Sometimes the holes in the plastic electric plug
need to be widened with a 4 mm drill.

8

10 mm Fixed Wrench

Insert the short bracket with the electric plug
attached into the two free ends of the silent
blocks previously attached to the engine in

Point 4. Tighten with washer and 6 mm nut.

9

3 mm Allen Wrench + 7 mm Fixed

Wrench

Insert the 4x30 screw into the coil. Attach the
coil in the specific bracket located on top the
main bracket and secure it with washer and 4
mm nut.

10

The stop cable end from the ignition is “male”.
The stop cable end from the battery is “male”
too.
We provide a “female-female” extension to link
both end.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

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11

Plug the two ends from the ignition to the coil.
Green cable goes in green plug.

12

3 mm and 5 mm Fixed Wrench

a. Attach the red cable to the electric starter

using the screw there is in it.
b. Unscrew the 5 mm Allen screw. Insert the
earth cable (black) plug into the screw and
screw firmly.

13

Cover both cables ends with the plastic covers
inserted in the cables.

14

10 mm Fixed Wrench

Attach the fuel pump to the free end of the
same silent block where the ground cable has

been attached in point 6. Secure it with 6 mm.
nut and washer provided.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

15

Flat Screwdriver

a. Remove the plastic cap from the depression

plug.

b. Insert the fuel line from the side of the fuel
pump into the depression plug in the crankcase

16

Flat Screwdriver

a. Remove the plastic cap from inlet manifold.

b. Remove carburettor from its box.

c. Fit the clamp provided together with the

carburettor over the inlet rubber manifold.

d. Insert the carburettor into the inlet rubber
manifold.

17

Flat Screwdriver

Ensure the carburettor is correctly seated, then
tighten the carburetor to the inlet manifold by
using the specific clamp.

18

Screw the air box mount to the carburettor

manually. Do not use any tool.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

19

Cross Screwdriver

Remove the top of the carburettor by
unscrewing the two screws.

20

Insert the throttle cable into the elbow on top
of the carburettor with the lead nut in.

21

8 mm Fixed Wrench

Tighten the carburettor throttle cable register
elbow.

22

Pass the throttle cable through the spring and
into the cut in the side of the plastic slide cover.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

23

Take the slide out of the carburettor.

24

Insert the lead at the end of the throttle cable
into the hole in the center of the slide.

25

Hook the lead nut in the slide by moving it
aside of the center.

26

Place the slide, plastic slide cover and spring
into the carburettor.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

27

Cross Screwdriver

Fix the top of the carburettor to the
carburettor by using the 2 screws unscrewed
before in Point 19

28

Insert the fuel line from the outlet on the
bottom of the fuel pump to the inlet on top
carburetor.

29

Insert the air tube into the intake silencer and
then place the plastic stone guard on top of the
air tube.

30

Insert the foam filter into the intake silencer.
There is a slot in the rubber manifold that
should be inserted in the intake silencer.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

31

Check the foam filter is properly fixed in intake
silencer. Wrong assembly will cause the loss of
the foam filter and intake silencer.

32

Flat Screwdriver

Attach the assembled intake silencer to the
adaptor and fix it by using the specific clamp
provided.

33

4 mm Allen Wrench + 10 mm Fixed

Wrench

Use the specific “S” bended bracket to connect
the intake silencer to the main bracket where
fuel pump is attached. Secure the intake silencer

by using one 6x25 screw (to the intake silencer)
and one 6x20 (to the bracket) screw, washer,

plastic spacer and nut.

34

Flat Screwdriver

Remove the plastic cap from the head.

Spark Plug Wrench
Tighten the spark plug in the engine head.
Tighten and loosen the spark plug 2/3 times to
allow the gasket to seat. Then tighten the spark
plug securely.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

35

Insert the coil cable into the rubber plug cup so
it is tight.
It is recommended to secure the coil cable by
using a cable tie.
Place the plug cap on to the spark plug and
push the plug cap down firmly.

36

Your engine is now ready to be installed to the
chassis.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

3. ENGINE/CHASSIS ASSEMBLY

1

5 mm Allen Wrench + 10 mm Fixed
Wrench

Place the sprocket in the sprocket carrier and
tighten with washer and nut.

2

8mm Allen Wrench

Now place the engine on the chassis. Tighten
the engine mount clamps to the engine mount
lightly enough to hold the engine in position.
Do not tighten completely

3

Straight Ruler

Align the rear sprocket (in the axle) with the
front sprocket (in the clutch bell). Then install
the chain of proper length. Chain length varies
with gear sizes.

4

To adjust chain tension, move the engine ahead
until the proper tension is reached. Proper
tension is around 1 cm. of free up and down
movements.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

5

17 mm Fixed Wrench

Once chain tension is correct, tighten mount
clamps completely and re-check the chain
tension again. Then set the engine stop to just
contact the engine mount, (if provided by the

chassis manufacturer.)

6

5 mm Allen Wrench

Attach the plastic guard bell cover to the
engine by using three 6x20 mm Allen screws.

7

Flat Pliers

By using flat pliers, very carefully, turn the two
carburetor overflow elbows on the carburettor
to point upwards.

8

Insert the plastic tube provided on to each one
of the carburettor overflow elbows.
The tube may be provided in one piece only. In
that case, cut the tube in half. The length of
each tube should be 40 cm. approx.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

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9

Place a recovery tank under the carburettor
and secure it to the chassis by using cable ties.
Make two holes on top of the cap and insert
the free ends of the tubes coming from the
overflow elbows. This container must be able
to vent to atmosphere.

10

Insert now the throttle cable into the outer.

11

Insert the free end of the throttle cable into the
register attached to the main rail of the chassis.

12

3mm Allen Wrench

Insert a clamp into the throttle cable and pass
the free end through the welded ring on the
throttle pedal. Then loop it around and insert
the free end of the cable into the to the clamp

again and tighten it. Clamp not supplied.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

13

Flat Screwdriver

Take the intake silencer off the carburettor by
unscrewing the clamp. It is not necessary to
unscrew the bracket. The intake silencer will
turn easily.

14

8 mm Fixed Wrench

Adjust the throttle cable by setting the pedal
stop on the chassis in order to get the pedal to
stop at the point where the slide in the
carburettor is fully open.

15

5 mm Fixed Wrench

Attach now the battery cradle to the chassis
main rail next to the seat using the specific
plastic clamp provided.
A battery mounting spacer plate may be

required to clear the brake cable.

16

4 mm Allen Wrench + 10 mm Fixed
Wrench

Remove relay from socket in the wiring loom.
Secure the wiring loom to the battery cradle
using a 6x25 mm Allen screw, bi conical washer,
2 plastic spacer, washer and 4 mm nut.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

17

Insert manually the relay into the female plug
in the wiring loom. Do not use any tool.

18

14 mm Fixed Wrench

Place the start bottom (Green) and the stop
bottom (Red) in the two slots located in the
front of the battery cradle. Secure them with
the specific nut attached in the cables.

19

Place the battery in the battery cradle. Insert
the battery cables in the battery plugs. Red
cable in red plug, black cable in black plug.
Secure the battery using the two rubber O.R.
provided.

20

Secure the relay with the specific spring
provided.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

21

Pass the main wire loom under the seat and
secure it to the chassis by using plastic cable
ties. Make sure there is no loose wiring that

may drag on the track.

22

Plug in the electric plug coming from the battery to
the other half located aside the engine.

23

a. Cover the inside of the RPM limiter box

cradle with the specific foam tape provided.
Fit a small piece of fuel line to the O.R as
illustrated in the picture and secure the RPM

limiter box to the cradle with the O.R.

b. Attach the cradle to the seat or the chassis.

c. Insert the female plug coming from the

ignition on the male plug in the RPM limiter
box.

24

Hook the two springs provided into the exhaust
manifold.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

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25

11 mm Socket Wrench

Before fitting the exhaust manifold remove the
exhaust gasket and the exhaust port cover.
Refit the exhaust gasket to the cylinder, then fit
the exhaust manifold by using the brass spacer

and the nuts. Tighten each nut alternatively.

26

Hook

Insert the muffler into the exhaust manifold. Fix
the muffler by hooking the free ends of the
spring into the rings welded to the muffler by
pulling them.

27

Hook

Place the muffler in the exhaust cradle that is
assembled on the chassis and pull the two
springs provided to fasten it.

28

Insert the fuel line from the fuel tank into the
fuel pump

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

4. STARTING AND BRAKE-IN

Only a proper break-in will insure the best performance out of your engine in the future and
guarantee its long and trouble-free life.

Break-in is required when an engine is new or has undergone a major service of the engine's main
parts (pistons, rings, cylinder or crankshaft).

1 Prepare fuel. Vortex engine works with commercial gasoline, leaded or unleaded, as well as

racing fuel, with minimum 95 ROM.
Mix oil and gasoline at 3% (i.e. 30cc of oil every 1.000 cc. of fuel).

2 Use a high quality 2-stroke oil specifically made for kart engines. We recommend Petronas Rok

Lube, however many others oils with the same features may be used. Check any requirements of
your ASN regarding the use of specific brand/type

3 Shake the can thoroughly to mix the fuel and the oil properly. Then fill the gas tank in your kart.

A mistake in measurements could result in engine damage.

4 Buttons: to start the engine press the green button. To stop the engine press the kill switch red

button.

5 To start a cold engine pull the choke lever up.

6 Press the start button (green) in order to allow the fuel pump-to-pump fuel to the carburetor.

7 Once the engine starts push the choke lever down.

8 Run the engine by accelerating intermittently to higher RPMs. Do not accelerate to full throttle.

9 Once the engine is warmed up, proceed to the track. By accelerating very carefully, the clutch

will engage and the kart will start moving forward.

10 Run the engine by alternating a few seconds on and off the throttle at ¾ of the opening.

Do not hold the throttle at a constant speed.
Continue this way for 5/6 laps.

11 Check everything on the kart is tighten properly. Be careful, engine and muffler are hot.

12 Return to the track and slowly increase the RPM and duration of the acceleration for

10/15min more. Intermittently open the throttle fully and then release it.

13 After 10/15 minutes of brake-in, your engine is ready for competition. During the break-in,

nuts and bolts tend to loosen. Once the engine is cold, check the torque of the exhaust, head, etc

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

5. SERVICING YOUR ENGINE

Good maintenance is essential for safe, economical and trouble-free operation. Here you will find
a maintenance schedule, routine inspection procedures and very simple maintenance procedures
by using basic tools. Some service tasks that are more difficult or needs special tools must be
performed by Vortex technicians or qualified mechanics.
Timing schedule periods are only indicative.

5.1. Maintenance Schedule and Adjustments

Carburettor

Cleaning

After every race/heat

Throttle Cable

Check

Every race

Spark Plug

Check
Change

Every Race
After 30 hours

Exhaust

Internal cleaning

Every 10 hours

Clutch

Check and cleaning
Change

Every 10 hours
After 30 hours

Piston

Change

After 30 hours

Chain

Change

After 10 hours

Cylinder

Honing

After 30 hours

Connecting Rod

Change

After 90 hours

Bottom End

Re-built

After 90 hours

5.2. Torque Chart

Cylinder Head Ø 8 mm Nut

kgm 1,8

Exhaust Manifold Ø 7 mm Nut

kgm 1,5

Crankcase Ø 6 mm Screws

kgm 1,2

Bendix cover Screws

kgm 0,8

Starter Gear Nut

kgm 6 (Use threadlocker)

Pinion Bell Ø 5 mm Screws

kgm 0,8

Ignition Nut

kgm 2,8

Pinion Bell Nut

kgm 2,8

Ignition Ø 5 mm Screws

kgm 0,8

Nylon crankshaft stuffer

kgm 0,8 (Use threadlocker)

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

5.3. Sizes and Measures

Tolerance Cylinder/piston

10,5

Timming

3mm

Piston Sizes

W240/MR01A

41,88

W240/MR03A

41,91

W240/MR06A

41,93

W240/MR09A

41,95

W240/MR11A

41,98

5.4. Chain

Lube the chain by spraying chain lube on the
chain while manually rotating the rear wheel.
To replace the chain, loosen the engine and
slide it back to release the old chain from the
sprocket. Reverse the procedure after installing
a new chain.

5.5. Throttle Cable

Lubricate the throttle cable each time the
engine is run. Also check, and adjust the cable
as needed, to assure the correct throttle and
that the throttle returns properly and opens full
size.
If the cable frays, it must be replaced.

5.6. Carburettor

Cleaning:

Fuel and oil may contain some kind of rubbish,
impurities, and/or residues.

1.Take the intake silencer off the carburettor by
unscrewing the clamp. It is not necessary to
unscrew the bracket. The intake silencer will
turn easily.

2.Disconnect the throttle cable from the
carburetor together with its spring and slide it.

3.Took the carburetor off the engine and open
the float chamber (22) by unscrewing the four
screws (23). Clean the parts, openings and
passages with compressed air. Check the float
chamber gasket (21) and eventually change it if
damaged.

4. Close the float chamber by screwing the four
screws (23) and re-place the carburettor in the
engine.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

5.Clean the inside of the intake silencer.

6. Attach the intake silencer assembly to the

adaptor.

7.Tighten it with the specific clamp. Wrong
assembly will cause the loss of the intake
silencer.

Changing main jet:

1.Take the intake silencer off the carburettor by

unscrewing the clamp. It is not necessary to
unscrew the bracket. The intake silencer will
turn easily.

2.Disconnect the throttle cable from the
carburetor together with its spring and slide it.

3.Took the carburetor off the engine and open
the float chamber (22) by unscrewing the four
screws (23). Clean the parts, openings and
passages with compressed air.

4.Unscrew the main jet (4) by using a cross
screwdriver. Place a new one. Be careful,
washer (18) has only one position. Wrong
assembling will cause totally black out of
carburettor.

5.Check the float chamber gasket (21) and
eventually change it if damaged.

6.Close the float chamber by screwing the four
screws (23) and re-place the carburettor in the
engine.

7.Clean the inside of the intake silencer.

8. Attach the intake silencer assembly to the

adaptor.

9.Tighten it with the specific clamp. Wrong
assembly will cause the loss of the intake
silencer.

5.7. Spark Plug

Cleaning:

Oils produce carbon deposits or residues that

Unplug the spark plug and clean it by using a
metal brush.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

make necessary the spark plug to be checked
and cleaned, at least every 5 hours.

Setting Plug Gap:

Use a specific spark plug gap gauge to set up
correct gap. Correct gap: 0,8 mm.

5.8. Exhaust

Cleaning:

Oils produce carbon deposits or residues that
make necessary the spark plug to be checked
and cleaned, at least every 10 hours.

1.Remove the muffler from the engine by
removing the 2 springs in the cradle and the 2
springs in the exhaust manifold.

2.Unscrew the 3 bolts in the exhaust terminal.

3.Warm up the pipe with a heat source and

remove any carbon deposits by means of a
metal brush.

5.9. Clutch and Starter Gear

Cleaning and/or replacing clutch:

1.Disassemble the clutch cover.

2. Take away the Bendix cover

3.Stop the clutch drum by using the special tool

designed by Vortex for this specific task.

4.Unscrew anticlockwise the nut on the clutch
drum (92). Remove the washer (91), clutch
drum (87) and roller bearing (90).

5. Unscrew the three 6x14mm Allen screws (79)
on the clutch.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

6.Unscrew clockwise the central nut (84) by
using a 24mm fixed wrench to remove it. Stop
the starter gear with the specific tool
manufactured by Vortex.

7.Take away the clutch (82) by using the
appropriate extractor.

8.Before assembling the new clutch, we
recommend to clean the clutch area and the
pinion bell with a solvent.

ASSEMBLING

9.Install the new clutch (82) on the crankshaft

by pushing lightly with your fingers and secure
it with the three 6x14mm Allen screws (79).
Use thread locker to secure them.

10.Put together again the elastic washer (83)
and the central nut (84) and tighten. Use

thread locker to secure the central nut.

11.After screwing the central nut place the
washer (85).

12.Grease the needle bearing (90) totally and
insert it on the crankshaft.

13.Place the clutch bell (87), the spacer (91)
and screw the nut (92). Use thread locker to
secure it.

14.Re-place Bendix cover.

15.Re-place the clutch cover.

Replacing Starter Gear

1.Disassemble the clutch cover.

2. Take away the Bendix cover

3.Stop the clutch drum by using the special tool

designed by Vortex for this specific task.

4.Unscrew anticlockwise the nut on the clutch
drum (92). Remove the washer (91), clutch
drum (87) and roller bearing (90).

5. Unscrew clockwise the central nut (84) by
using a 24mm fixed wrench to remove it. Stop
the starter gear with the specific tool
manufactured by Vortex.

6.Take away the clutch (82) together with the
starter gear (80) by using the appropriate
extractor.

7. Unscrew the three 6x14mm Allen screws (79)

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

on the clutch.

8.Before re-assembling, we recommend to
clean the area with a solvent.

ASSEMBLING

9.Screw the new starter gear (80) to the clutch

(82) by using three 6x14mm Allen screws (79).
Use thread locker to secure them.

10.Insert the starter gear and clutch on the
crankshaft by pushing lightly with your fingers.

11.Put together again the elastic washer (83)
and the central nut (84) and tighten. Use

thread locker to secure the central nut.

12.After screwing the central nut place the
washer (85).

13.Grease the needle bearing (90) totally and
insert it on the crankshaft.

14.Place the clutch bell (87), the spacer (91)
and screw the nut (92). Use thread locker to
secure it.

15.Re-place Bendix cover.

16.Re-place the clutch cover.

5.10. Pinion

KSNZ allows the use of Z11 or Z10 pinions.
Standard assembling is Z11.

1.Disassemble the clutch cover.

2.Stop the clutch drum by using the special tool

designed by Vortex for this specific task.

3.Unscrew anticlockwise the nut on the clutch
drum (92). Remove the washer (91), clutch
drum (87) and roller bearing (90).

4.Unscrew the four bolts inside the drum.

5.Place the new pinion on the bell and secure it

with the 4 bolts. Use thread locker to secure
them.

Be aware if you are placing a Z10 pinion, a
specific spacer is needed.

6.Install roller bearing and the spacer. Grease

the roller bearing properly.

6.Re-place the clutch drum, the washer and the
nut. Tighten the nut by turning it to the left.
Use thread locker to secure it.

7.Re-place the clutch cover.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

5.11. Cylinder Head

Oils produce carbon deposits or residues that
make necessary the spark plug to be checked
and cleaned, at least every race.

Be aware, cylinder head volume may be
changed after the race, Carbon deposits may
cause variations on the cylinder head volume.

In order to perform this job, we highly
recommend taking the engine off the chassis.
However, you may do the job even with the
engine mounted.

1. Unscrew the spark plug (4).

2.Unscrew the 4 nuts on top of the head (3).

3.Remove the head by pulling it up carefully.

4.Clean the combustion chamber using a rag

moistened with gasoline or solvent.

ASSEMBLING

5.Check copper gasket on top of cylinder (5).

This gasket may provoke changes in the
combustion chamber volume.

6.Re-place cylinder head carefully in the four
studs (10).

7.Insert brass washers (2) and nuts (3).

8.Tighten cylinder head with the proper tool

and torque.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

5.12. Cylinder

Every 30 hours cylinder must be honed.

In order to perform this job, we highly
recommend taking the engine off the chassis.
However, you may do the job even with the
engine mounted.

1.Take away the muffler from the engine by

removing the 2 springs in the cradle and the 2
springs in the exhaust manifold.

2.Remove the carburettor from the engine by
unscrewing the specific clamp.

3.Unscrew the 4 nuts on top of head (3).

3.Remove the head by pulling it up carefully.

4.Remove the cylinder with one hand by pulling

it up. To avoid contact with the crankcase, use
the other hand to hold the connecting rod.

Whenever you disassemble the cylinder, we
recommend replacing the cylinder gasket (9).

ASSEMBLING
Check the tolerance between piston and
cylinder. Wrong tolerance may cause serious
damage.

5.Place a new gasket (9) into the four studs

(10).

6.Insert cylinder into the four studs carefully.

7.Check the rubber O.R. (6) and brass gasket (5)

and eventually re-place them with new ones.
Brass gasket may provoke changes in the
combustion chamber volume.

8.Re-place the cylinder head carefully in the
four studs.

9.Insert brass washers (2) and nuts (3).

10.Tighten cylinder head with the proper tool

and torque.

Important: After honing the cylinder and
eventually changing the piston, the engine
must go through another break-in period. See
"Starting and Break-in".

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

5.13. Piston

Oils produce carbon deposits or residues that
make necessary the spark plug to be checked
and cleaned, at least every race.

Be aware, cylinder head volume may be
changed after the race, carbon deposits may
cause variations on the cylinder head volume.

Every 30 hours piston must be replaced.

In order to perform this job, we highly
recommend taking the engine off the chassis.
However, you may do the job even with the
engine mounted.

1.Take away the muffler from the engine by

removing the 2 springs in the cradle and the 2
springs in the exhaust manifold.

2.Remove the carburettor from the engine by
unscrewing the specific clamp.

3.Unscrew the 4 nuts on top of head (3).

3.Remove the head by pulling it up carefully.

4.Remove the cylinder with one hand by pulling

it up. To avoid contact with the crankcase, use
the other hand to hold the connecting rod.

Whenever you disassemble the cylinder, we
recommend replacing the cylinder gasket.

5.Remove the 2 piston pin circlips (65) by

squeezing the ends together with the needle­nose

6.Hook the connecting rod each side with two
fingers.

7.Push the piston pin (66) off the piston by
using a proper tool.

8.In order to avoid damages pull the piston up
with one hand while holding the connecting rod
with the other.

9.Take the roller bearing (70) off the
connecting rod.

ASSEMBLING
Check the tolerance between piston and
cylinder. Assemble ONLY a new piston with
the right tolerance. Wrong tolerance may
cause serious damage.

10.Grease and place a new roller bearing (70),

if needed, on the connecting rod.

11.Insert a new piston in the connecting rod.
The arrow marked on top of it, must face the
exhaust port.

12.Insert the piston pin into the piston.

13.Insert piston pin circlips on each side of the
piston. Be aware, wrong assembly of piston

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

pin circlips may cause important damage.

14.Place the piston ring in the piston and check

both ends close properly against the brass pin
inserted in the piston.

15.Place a new gasket (9) into the four studs
(10).

16.Insert the cylinder into the four studs
carefully.

17.Check the rubber O.R. (6) and the copper
gasket (5) and eventually re place them with
new ones. Brass gasket may provoke changes in
the combustion chamber volume.

18.Re-place the cylinder head carefully in the
four studs.

19.Insert brass washers (2) and nuts (3).

20.Tighten cylinder head with proper tool and

torque.

Important: After changing the piston, the
engine must go through another break-in
period. See "Starting and Break-in".

5.14. Connecting Rod

Every 60 hours the roller cage must be changed. During this operation is good use to check, and
eventually replace the connecting rod, too.

Due to special tools required, this operation must be performed by the Vortex technicians or
qualified mechanics only.

5.15. Bottom End

Bearings must be checked, and eventually replaced, after 60 hours of use.
Bearings must be assembled or reassembled, with name and type facing each others.

Due to special tools required, this operation must be performed by the Vortex technicians or
qualified mechanics only.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

6. ENGINE EXPLODED VIEW AND PARTS LIST

.

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

Dell’Orto Carburettor

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

Parts List

1

W010/MR

Air head 60cc

2

W560

Head washers 8,5 x 15 x 8

3

W530/12

Head-nut high-set m8

4

W003

Spark plug ngk b10 eg

5

W631/01MR

Copper head gasket 42,2 x 62,4 x 0,1

5

W631/02MR

Copper head gasket 42,2 x 62,4 x 0,2

6

W620/MR

O-ring head viton

7

W020/1MRC

Cylinder 60cc complete

8

W470

Exhaust stud bolt m7 x 32

9

W610/1MRC02

Cylinder basis gasket 0,2

9

W610/1MRC03

Cylinder basis gasket 0,3

9

W610/1MRC04

Cylinder basis gasket 0,4

9

W610/1MRC05

Cylinder basis gasket 0,5

10

W461/1VLC

Cylinder stud bolt m8 x 142

11

W2050/MR

Inlet manifold phbg 18

11

W2050/BR

Inlet manifold phbn 14

12

W825/1MR

Carburettor clamp d.23-35mm

13

V.TCE6X16

Socket-head screw m6 x 16

14

W820/BR

Dellorto carburettor phbn 14ms

14

W820/MR

Dellorto carburettor phbg 18b

15

W981400

Connector

16

W540/RVA

Exhaust fix. High set nut

17

W565

Exhaust washer d.8 x 12 x 1,5

18

W750/1MR

Exhaust manifold mr/t 60cc

19

W670/MR

Exhaust gasket

20

WA063

Head control template mini rok

21

WA064

Carburettor gap control template

32A

W050/MRC

Complete crankcase 60cc with bearing

33

V.TCE6X40

Socket head screw m6 x 40

34

V.TCE6X45

Socket-head screw m6 x 45

35

W075/1

Crankcase dowel 10 x 10,5 x 6,5

36

W10267

Copper gasket d. 8 x 12 x 1

37

W800

Depression pipe fitting m8 hexagonal

38

W300/MR

Insert 6204 c4

39

W310

Oil seal fpj 20 x 35 x 7 double lip

40

W940/ROK

Starter 50589

41

W019

Cylindrical pin 6x18

42

W924

Roller case bk0808

43

W916/ROK

Starter driving gear 50589

44

W910/ROK

Starter driving gear cover

45

V.TCE6X20

Socket-head screw m6 x 20

46

W960/RKT

Transmission starter support

47

V.TCE6X30

Socket-head screw m6 x 30

48

V.TCE6X65

Socket head screw m6 x 65

49

W972/MR

O.r.4200 starter support

50

W970/MR

Starter support d.50

51

W975/MR

Starter support spacer

64

W240/MR01A

Complete piston 41,88

64

W240/MR03A

Complete piston 41,91

64

W240/MR06A

Complete piston 41,93

64

W240/MR09A

Complete piston 41,95

64

W240/MR11A

Complete piston 41,98

65

W280/MR

Circlip d.12,00

66

W270/MRA

Piston pin mini rok

67

W140/MR

Magn.s.h. Crankshaft 60cc

68

W122

Ignition key 2,5 x 3,7 x 10

69

W220

Silver-plated cage d.18 x 24 x 15

70

W290/MR

Piston cage 12 x 16 x 15,5

71

W200/1MR

Crankshaft crankpin d.18 x 40,6

72

W230/MR

Conrod engine 60cc

73

W522/10

Flathead screw m5 x 10

74

W160/MR

Nylon crankshaft stuffer

75

W121

Dragging sprocket key 3 x 3,7 x 10

76

W150/MR

H.crankshaft sprocket side 60cc

77B

W190/MR

Complete conrod 60cc

78C

W130/1MR

Complete crankshaft mini rok

79

W510/14

Socket-head screw m6 x 14

80

W1753/MR

Starting driven gear z 62

81

W1766/1ROK

Cylindrical pin 6 x 10

82

W1751/1KFC

Clutch rotor kf with pin

83

W1708

Belleville washer d.16,3 x 31,5 x 1,5

84

W1727

Clutch body fix nut m16 x 1 thr.

85

W1726/1

Washer 2,0 mm mini-kf

86

W523/08

Flathead screw m5 x 8

87

W1773/MR2

Bare clutch housing mini

88

W1766/ROK

Roll d.5 x 5

89

W690/MR11

Mini rok sprocket z11

90

W1715

Clutch cage k12 x 15 x 15

91

W1777/1ROK

Clutch washer d.10,1 x 18,8 x 2

92

W696/MR

Sprocket nut 60cc

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

93D

W1750/1MR

Compl.clutch rotor with gear

94E

W1763/MR11

Compl.clutch housing w/sprocket z11

94E

W1763/MR10

Compl.clutch housing w/sprocket z10

105

W410/MR

Selettra coil mini rok

106

W531/06

Hexagonal nut m6 x 1

107

W570/12

Flat washer d.6 x1 2 x 1,5

108

W2052/MR

Fuel pump support plate

109

W440

Coil fix. Silent - block

110

W11023

Vacuum pump

111

W420/2

Spark cap

112

W529/0108

Hexagonal nut m10 x 1

113

W1777/MR

Ignition washer d.10,4 x 18 x 2

114

V.TCE5X20

Socket-head screw m5 x 20

115

W580/10

Washer d.10 x 5,5 x 0,3

116

W407/MR

Bare ignition mini rok

117

W524/14

T.c.e.i. Screw m5 x 14

118

W068/MR

Ignition support

119

0074.C0

Fuel tube 6 x 9

121

W780/1MR

Engine 60cc exhaust

122

W10925

Muffler springs

133

W2111/ROK

Relay deviator

134

W2110/ROK

Starting relay 12v - 70a

135

W2116/ROK

Red starter button on-off

136

W2115/ROK

Green starter button

137

W2113/ROK

Fixing button plate

138

W521/14

Roundhead screw m5 x14

139

W435/MR

Mini rok wiring adapter

140F

W2125/ROK

Complete starting support

141

W2130/ROK

Accumulator charger italy

141

W2131/ROK

Accumulator charger japan-u.s.a.

142

WA052/KF

Clutch puller

143

WA061

Clutch nut fix key

144

WA062

Sprocket disassembling tool sr/mr

145

W991

Accumulator fg 20722

146

0096.00

Belt or 4437

147

W2121/ROK

Accumulator support rubber

148

W2122/ROK

Accumulator support

151

W856/MR

Mini rok filter support

152G

W2122/ROKC

Complete accumulator support

153

W850/1MR

Intake filter 60cc engine

161V

W820/MR

Dellorto carburettor phbg 18b

162H

W53036-78

Tube 90° kit

163I

W53031-78

Chamber mixture cover kit

164

W9597-61

Gas valve spring

165

W14958-21

Conical needle fastener fix plate

166

W9596211

Conical needle fastener

167

W959523

Conical needle w23 x 08

168

W947540

Gas valve 40 x 64

169

W148850

Jet min. 50

170

W950160

Jet 60

171

W52526-77

Gaskets kit

172

W9450-80

Float

173

W11836-36

Float chamber fixing screw

174

W9444-96

Float chamber

175

W9506-22

Float peg

176

W283805

Gas needle closing

177

W148697

Jet max. 97

178

W9779-52

Bottom

179

W9511266

Spray nozzle an 266

180L

W53027-78

Needle gas valve kit

181M

W53024-78

Adjustment minimum screw kit

182

W9538-64

Starting device

192Z

W820/BR

Dellorto carburettor phbn 14ms

193

W7526-36

Cover fixing screw

194

W14166-53

Chamber mixture cover

195

W15058-61

Gas valve spring

196

W13687-21

Conical needle retainer

197

W1536240

Gas valve 40

198

W13681-21

Conical needle fastener

199

W1625011

Conical needle

200N

W53004-78

Starter kit

201

W14056-37

Adjustment minimum air screw

202

W1411-61

Spring adjustment min. Air screw

203P

W53086-78

Adjustment gas valve screw kit

204

W14671212

Spray nozzle ga 212

205

W641375

Jet max. 75

206

W621750

Starting device 50

207

W1160038

Jet min. 38

208

W52620-77

Gaskets kit

209O

W53053-78

Float kit

210

W13678-96

Float chamber

211

W13709-36

Float chamber fixing screw

VORTEX FACTORY: Via E. Fermi, 5 – 27040 Campospinoso (PV)– ITALY – Tel. [phone]

OTK KART GROUP srl

Via dei Soprini, 16 – 25080 PREVALLE (Brescia) ITALY-Tel. [phone] – Fax [phone]

7. CONTACTS

Manufacturer

Vortex Factory
Via E. Fermi 5
27040 – Capospinoso
Italy
Tel: [phone]

[e-mail]

New Zealand Importer

Supreme Kart Supplies
78 Hurlstone Drive
1146485 NEW PLYMOUTH
Tel: [phone]

[e-mail]

ASN

Kart Sport New Zealand
45 Mt Wellington Highway
Auckland 1060
Tel: [phone]

www.kartsport.org.nz