KTM LC4 400-660LC42003 engine. Manual - part 8

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

5-19D

Shift mechanism support

– If the grooved ball bearing 

1

of the shift roller must be exchanged,

press the new grooved ball bearing all the way into the seat.

! 

CAUTION

!

T

O PREVENT DAMAGING OF THE SHIFT MECHANISM SUPPORT

, 

DO NOT APPLY

EXCESSIVE FORCE WHEN INSERTING THE GROOVED BALL BEARINGS

.

– Apply Loctite 243 to the screw and fix the bearing.
– The new needle bearing of the kickstarter shaft 

2

has to be pressed

in flush.

Balancer shaft

Check bearing seat

A

for wear and tear.

Check three allan head bolts

3

for tight fit.

Disassembling and reassembling the water pump

Remove the water pump cover 

4

together with the gasket.

– Remove circlip 

5

from the water pump shaft 

6

and pull shaft and

water pump wheel 

7

out of the grooved ball bearings.

– If grooved ball bearings 

8

are replaced, remove circlip 

9

and shaft

seal ring 

bk

and press out bearing.

– Properly lubricate new grooved ball bearings and press in to stop

with the open sides facing each to them.

– Mount circlip 

9

.

– Cover new shaft seal ring with Loctite 648 and press in with the

printing facing outward.

– Lubricate water pump shaft and mount carefully so as to not

damage sealing lips of shaft seal ring and check for smooth working.

– Mount circlip 

5

and water pump cover 

4

with gasket.

– Finally, remove silicone from the sealing flange and mount 2 new 

O-rings 

bl

.

5

4

6

10

11

7

9

8

1

2

A

3

5-20D

Important note regards working on transmission

– Fix the main shaft or countershaft, respectively, in the vise (use

special vise jaws to avoid damaging of the shafts) and remove the
gear wheels.

– Clean and check all parts.

Always use new lock washers when performing repair work on the
transmission !

Check the tooth profiles of transmission shafts and sliding gears for
signs of wear.

Slide the sliding gears onto the transmission shafts and check the
toothing for easy operation.

Check the pivot points of the transmission shafts.

Mount the idler gears with the bearings on the transmission shafts and
check for clearance.

Check the needle bearings of the idler gears.

Assembling the main shaft

– Mount the main shaft in a vise with the gearwheel facing

downwards (use protective jaws).

– Mount the needle cage 

1

and slide the 3rd gear 

2

with the shift

dogs facing upwards.

– Mount stop disc 

3

(22.7x32x1.5 mm) and the circlip 

4

with the

sharp edge facing up.

– Mount 4th gear 

5

with the shift groove facing down.

– Secure it with the circlip 

6

with the sharp edge down and mount

the stop disc 

7

(22.7x32x1.5 mm).

– Mount needle cage 

8

and 5th gear 

9

with the shift dogs down. 

– Mount 2nd gear 

bk

and stop disc 

bl 

(20.2x35x1 mm). 

NOTE: Check all gears for smooth operation.

1

5

6

7

8

9

10

11

2

3

4

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

5-21D

Important note regards working on transmission

– Fix the main shaft or countershaft, respectively, in the vise (use

special vise jaws to avoid damaging of the shafts) and remove the
gear wheels.

– Clean and check all parts.

Always use new lock washers when performing repair work on the
transmission !

Check the tooth profiles of transmission shafts and sliding gears for
signs of wear.

Slide the sliding gears onto the transmission shafts and check the
toothing for easy operation.

Check the pivot points of the transmission shafts.

Mount the idler gears with the bearings on the transmission shafts and
check for clearance.

Check the needle bearings of the idler gears.

Assembling the counter shaft

– Mount counter shaft in vise with collar facing downwards.
– Oil and mount needle cage 

1

. 

– Slide 2nd gear 

2

over needle cage with collar facing downwards.

– Mount stop disc 

3

(22.7x32.0x1.50 mm) with clearance towards

gear wheel and circlip 

4

with sharp edge facing upwards.

– Mount 5th gear 

5

with shift groove facing upwards.

– Fit circlip 

6

with sharp edge down and stop disc 

7

(22.7x32.0x1.50

mm).

– Mount needle cage 

8

and fit 4th gear 

9

with shift dogs facing up. 

– Mount stop disc 

bk

(22.7x32.0x1.50 mm) and circlip 

bl

with sharp

edge facing up. 

– Fit 3rd gear 

bm

with shift groove down and mount stop disc

(22.2x35.0x1.50 mm) 

bn

.

– Mount needle cage 

bo

, 1st gear 

bp

with collar facing up and fit stop

disc (20.2x35.0x1.0 mm) 

bq

.

NOTE: A roller bearing was installed in the 660 SMC model, thus a stop
disc is unnecessary.

Check all gears for smooth operation.

1

3

2

4

5

6

7

8

9

10

11

12

13

14

15

16

5-22D

Removing the intermediate gear

– Remove the starter cover.
– Pull out the bearing bolt 

1

.

– Remove the intermediate gear and the needle bearing.
– Check the parts for signs of wear.

– Insert the intermediate gear with the collar downward into the

housing for preassembly. 

– Oil the needle bearing and install it with the bearing bolt.
– Do not yet replace the starter cover.

Checking the freewheel

– Insert the freewheel gear 

2

into the freewheel. 

– The freewheel gear must turn clockwise.
– The freewheel gear must lock without empty run if turned

anticlockwise.

– Check the reduction gear 

3

and the needle bearings for signs of

wear.

– Check the needle bearing of the freewheel gear for signs of wear.

Replacing the freewheel hub

– Squeeze the spreader ring 

4 

with the circlip pliers and remove it

together with the freewheel.

– Check the freewheel segments for signs of wear.
– Check the freewheel hub sections at the freewheel running surface

for signs of wear.

– Heat the flywheel to a temperature of approx. 80° C (176° F) and

remove the 6 bolts.

! 

CAUTION

!

M

AKE SURE THAT THE FLYWHEEL IS NOT HEATED BEYOND

80° C (176° F) 

TO

AVOID LOOSENING OF THE MAGNETS

.

– Carefully tap the side of the  freewheel hub with a plastic hammer

and take off the freewheel hub.

– Apply Loctite 648 to the flange surface 

A

of the flywheel and the

freewheel hub.

– Mount the freewheel hub on the flywheel.
– Apply Loctite 648 to the thread of the bolts and tighten them

crosswise (18 Nm).

! 

CAUTION

!

A

LWAYS USE NEW BOLTS

(12.9) 

AND APPLY

L

OCTITE

648 

TO THE THREADS

.

– Thoroughly oil the free-wheel and  insert it into the freewheel hub.
– Insert the spreader ring into the groove with a pair of circlip pliers

and make sure that it properly rests in the groove.

Electric starter motor

– The starter showed only slight signs of wear after 10.000 starting

processes, and exchanging individual parts must be considered
uneconomical. Therefore, such work is not described in the present
documentation.

– Exchange the O-ring 

5

at the starter flange (incl. in the gasket set).

1

4

A

2

3

5

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

LOCTITE 648

LOCTITE 648

LOCTITE 243  

LOCTITE 243

SILICON

5-23D

Checking the stator and the pulse generator (Kokusan 4K2)

Use an ohmmeter to perform the following measurements:

NOTE: The measuring must be performed at a temperature of 20° C.
Otherwise significant deviations must be expected.

Replace the stator and/or the pulse generator if the measured values
deviate significantly from the setpoint values or in the case of continuity
between one of the cables and ground.

Replacing the stator (Kokusan 4K2)

– Loosen the 3 bolts and remove the stator.

– Insert a new stator into the ignition cover.
– Apply Loctite 243 to 3 new bolts and tighten the bolts.
– Insert the cable guide in the opening provided for that purpose in

the ignition cover.

Ignition (Kokusan 4K2)

General information
The measurements described below will only reveal severe
problems. Coil short circuits leading to weak ignition sparks
or low generator output, respectively, can only be detected
with the help of an ignition test bench. In the case of
malfunction always check the cables and the plug and socket
connections of the ignition system first.
Make sure to select the correct measuring range when
performing measurements.

MEASUREMENT

CABLE COLORS

RESISTANCE

red/black – black/red

Stator

yellow – black/red

0.45 – 0.56 Ω

yellow – red/black

Pulse generator

white – green

80 – 120 Ω

Checking the stator (SEM)

Perform the measurements indicated to the left with an ohmmeter.

NOTE: The measuring must be performed at a temperature of 20° C.
Otherwise significant deviations must be expected.

The stator must be exchanged if any of the measured values deviates
significantly from the respective nominal value or in the case of
continuity between one of the cables and ground.

Replacing the stator (SEM)

– Remove bolt 

1

with retaining bracket.

– Remove the three clamp bolts 

2

and lift the stator out of the

ignition cover.

– Mount the new stator in such a way that the timing mark 

A

is

visible in the checking hole on the rear side.

– Apply Loctite 243 to the threads of the bolts 

2

and insert the bolts

without, however, tightening them yet.

– Apply Loctite 243 to the thread of bolt 

1

, turn the stator clockwise

all the way to the stop.

– Fix the cable strand with retaining clips and insert the rubber cable

guide into the opening provided for that purpose.

– Turn the stator until the mark becomes visible in the peephole. Then

tighten the bolts 

2

.

5-24D

Ignition (SEM)

General information
The measurements described below will only reveal severe
problems. Coil short circuits leading to weak ignition sparks
or low generator output, respectively, can only be detected
with the help of an ignition test bench. In the case of
malfunction always check the cables and the plug and socket
connections of the ignition system first.
Make sure to select the correct measuring range when
performing measurements.

1

2

A

+ POLE

– POLE

MEASURE VALUE

black

red

1.7 kΩ

red black

1.7 

kΩ

black green

165 

Ω +/- 20 Ω

green

red

1.7 kΩ

yellow

yellow

1.0 Ω

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

5-25D

Installing a new stator (Kokusan 4K-3)

– Remove the 2 bolts 

1

and take the cover plate 

2

out of the ignition

cover.

– Remove the 2 bolts 

3

of the pulse generator and the 2 bolts 

4

of

the stator.

– Undo bolt 

5

and  take the retaining platelet out of the ignition

cover. Take the stator and the pulse generator out of the ignition
cover.

NOTE: When reassembling the unit, degrease and apply Loctite 243 to
the threads of all bolts.

– Put the new stator into the ignition cover and fix it with the two

bolts 

4

.

– Position the pulse generator in the ignition cover and fix it with the

two bolts 

3

.

– Put the cable guide into the recess provided for this purpose and fix

the cover plate 

2

with the two bolts 

1

.

– Position the wiring harness, taking care to avoid tension, and use the

retaining platelet and the  bolt 

5

to fix it in the ignition cover.

Ignition (Kokusan 4K-3)

General information
The measurements described below will only reveal severe
problems. Coil short circuits leading to weak ignition sparks
or low generator output, respectively, can only be detected
with the help of an ignition test bench. In the case of
malfunction always check the cables and the plug and socket
connections of the ignition system first.
Make sure to select the correct measuring range when
performing measurements. 

Checking the stator (Kokusan 4K-3)

Use an ohmmeter to perform the following measurements.

Note: The measuring must be performed at a temperature of
20° C. Otherwise significant deviations must be expected.

Replace the stator if the measured values deviate significantly
from the setpoint values.

LOCTITE 243

LOCTITE 243 

LOCTITE 243

1

1

2

3

3

4

4

5

Ignition

Measure

Cable colours

Resistance

Pulser coil

red – green

100 Ω

 20%

4K-3

Stator

black/red – red/white

12,7 Ω

 20%

Charging coil

ground – yellow

0,65 Ω

 20%

white – yellow

0,16 Ω

 20%

MOUNTING THE KICKSTARTER UNIT  . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-2
MOUNTING TRANSMISSION AND SHIFT MECHANISM  . . . . . . . . . . . . . .6-2
ADJUSTMENT OF RETURN SPRING  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-4
PRETENSIONING OF THE STARTER SPRING  . . . . . . . . . . . . . . . . . . . . . . .6-4
MOUNTING CRANKSHAFT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-4
ASSEMBLY OF ENGINE HOUSING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-5
MOUNTING OIL FILTER  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6
MOUNTING THE ENGINE SPROCKET  . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6
MOUNTING THE TIMING GEAR AND THE TIMING CHAIN  . . . . . . . . . . . .6-7
MOUNTING THE OIL PUMPS  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-7
MOUNTING THE BALANCER SHAFT AND THE PRIMARY PINION  . . . . . . .6-8
MOUNTING THE CLUTCH  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-8
MOUNTING THE CLUTCH DISCS  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-9
INSTALLING THE CLUTCH RELEASE SHAFT  . . . . . . . . . . . . . . . . . . . . . . . .6-9
ADJUSTING THE CLUTCH RELEASE  . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-10
MEASURE DIMENSION „Y“  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-10
MOUNTING PISTON AND CYLINDER  . . . . . . . . . . . . . . . . . . . . . . . . . . .6-10
MOUNTING THE CYLINDER HEAD  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-11
MOUNTING THE CAMSHAFT, TIMING MARKS . . . . . . . . . . . . . . . . . . . .6-12
MOUNTING THE WATER PUMP  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-13
MOUNTING THE CYLINDER HEAD TOP SECTION  . . . . . . . . . . . . . . . . .6-14
MOUNTING THE AUTOMATIC TENSIONER  . . . . . . . . . . . . . . . . . . . . . .6-14
AUTOMATIC DECOMPRESSION TESTING . . . . . . . . . . . . . . . . . . . . . . . .6-14
ADJUSTMENT OF VALVE CLEARANCE  . . . . . . . . . . . . . . . . . . . . . . . . . .6-15
MOUNTING THE CLUTCH COVER  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-15
MOUNTING THE ELECTRIC STARTER DRIVE  . . . . . . . . . . . . . . . . . . . . . .6-16
MOUNTING THE IGNITION (KOKUSAN)  . . . . . . . . . . . . . . . . . . . . . . . .6-16
ADJUSTING THE PULSE GENERATOR  . . . . . . . . . . . . . . . . . . . . . . . . . . .6-17
MOUNTING THE IGNITION (SEM)  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-17
ADJUSTMENT OF IGNITION POINT (SEM)  . . . . . . . . . . . . . . . . . . . . . . .6-18
MOUNTING THE EPC WIRING HARNESS  . . . . . . . . . . . . . . . . . . . . . . . .6-18
MOUNTING THE IGNITION (KOKUSAN 4K-3)  . . . . . . . . . . . . . . . . . . . .6-19
ADJUSTMENT OF IGNITION POINT (KOKUSAN 4K-3)  . . . . . . . . . . . . . .6-19
MOUNTING THE OIL HOSES  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-20
MOUNTING THE CLUTCH RELEASE LEVER  . . . . . . . . . . . . . . . . . . . . . . .6-20
MOUNTING THE ELECTRIC STARTER MOTOR  . . . . . . . . . . . . . . . . . . . .6-20
MOUNTING THE WATER HOSES  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-20
POURING IN ENGINE OIL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-21
MOUNTING THE KICKSTARTER AND THE SHIFT LEVER  . . . . . . . . . . . . .6-21

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

ASSEMBLING THE ENGINE

INDEX

6-1D

6