KTM LC4 400-660LC42003 engine. Manual - part 9

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

– Place left-hand housing half in engine work stand.

Mounting the kickstarter unit

– Insert stop disc (22.2x35x2 mm), starter gear 

1

, needle bearing and

stop disc 

2

(22.2x30x1.5 mm) into housing.

– Insert the pre-assembled kickstarter shaft into the bearing seat,

putting it through the starter gear. Make sure that the starter spring
slips into opening 

A

of the housing.

Mounting transmission and shift mechanism

– Insert stop disc (20.2x35x1 mm), 1st gear wheel 

3

with collar facing

down into the housing and the needle bearing into the idler gear. 

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

– Mount transmission shafts together and slightly turn them.

– Grease the driving pins of the shift forks and mount the shift rollers 

4

.

– Hook shift fork with legs of same length in the sliding gear of the

main shaft. 

– Fit the other two shift forks into the gears of the counter shaft,

paying attention to the marks applied during disassembly.

! 

CAUTION

!

U

SED SHIFT FORKS SHOULD BE MOUNTED IN THE SAME SLIDING GEAR AS BEFORE

.

6-2D

1

2

A

3

4

– Insert shift roller 

1

into the housing with the holder for the locking

piece facing up.

– Hook the shift forks into the shift roller and mount shift rails 

2

+ 

3

.

The shorter shift rail 

3

must be fitted to the main shaft.

– Before mounting the shift mechanism support, check whether the

two dowels  have been fitted.

– Mount shift mechanism support, secure the two bolts 

4

with Loctite

243 and tighten.

– Put the washer (6.2x18x2 mm), the locking lever, the locking spring

bushing and the locking lever spring onto the third bolt.

– Apply Loctite 243 to the thread of the bolt and mount it.

– Pull locking lever 

5

away from the shift roller.

– Put the shift drum locating device 

6

onto the shift roller, apply

Loctite 243 to the thread of the bolt and fix the shift drum locating
device.

– Oil the O-rings and grease the shank of the shift shaft.
– Slide preassembled shift shaft into kickstarter shaft.
– At the same time, push back the slide plate 

7

and make sure that

the ends of the return spring 

9

are resting against the centering cup

of the shift mechanism support 

8

.

6-3D

1

2

3

4

4

5

6

7

8

9

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

6-4D

Adjustment of return spring

– Engage second or third gear.
– Check free travel of slide plate and check shift pin play.
– The free travel of the slide plate is the path this component travels

until the shift roller is moved. The return spring pressure will be felt.
Proceeding from the basic position, this free travel 

A

should be 

identical for upward and downward movement. 

– If necessary, the free travel must be readjusted by adjusting the

return spring.

– For this purpose, remove the shift shaft and bend the return spring

by an appropriate amount at points 

B

using a pair of pliers. Refit

shift shaft. After the shifting shaft has been fitted, the return spring
must rest against shift pin 

1

and against the centering cup on the

shift mechanism support.

– If necessary, bend the return spring accordingly.

Pretensioning of the starter spring

– Fit kickstarter onto kickstarter shaft, turn one revolution in starting

direction and hold in this position. 

– Mount the stop bolt 

2

together with a new seal ring and tighten it

manually.

! 

CAUTION

!

I

T MUST BE POSSIBLE TO MOUNT THE STOP BOLT WITHOUT APPLYING EXCESSIVE

FORCE

. I

F IT IS NOT POSSIBLE TO MOUNT THE STOP BOLT MANUALLY

, 

TURN THE

KICKSTARTER SHAFT FURTHER AGAINST THE FORCE OF THE SPRING UNTIL THE STOP
BOLT CAN BE MOUNTED

.

– Move kickstarter to stop and remove.
– Tighten stop bolt 

2

with 50 Nm.

– Place O-ring 

3

(22x1 mm) and inner ring 

4

of roller bearing on the

counter shaft with the collar facing the gear.

– Mount stop disc 

5

(20.2x35x1 mm) onto the main shaft.

Mounting crankshaft

– Grease the shaft seal ring of the crankshaft and thoroughly oil the

roller bearing of the crankshaft.

– Fit mounting sleeve onto crankshaft and place crankshaft into

bearing.

1

B

2

3

4

5

6-5D

Assembly of engine housing

– Make sure both dowels are in place in the left housing half, and put

gasket on the sealing surface. Use a little bit of grease to hold the
gasket in place.

– Grease all shaft seal rings in the left side of the housing.
– Oil all bearings in the right side of the housing and put on the

housing half. If necessary, tap lightly with a plastic mallet and turn
transmission shafts.

– Check to make sure that the gasket is in the proper position before

final assembly. 

– Grease housing bolts (threads and contact surfaces of bolts heads).

Insert bolts and assemble the housing (see sketch for bolt lengths).

– Check all the shafts for smooth operation before and after tightening

with 7-8 Nm.

– Mount case in mounting rack and check function of gear-change by

engaging all gears. 

– Check crankshaft axial clearance (0.03 - 0.12 mm) (0.0012 - 0.0047

in) and fit crankshaft locking bolt.

NOTE: On Adventure-models bolts M6x35 are used instead of the two
upper bolts M6x30.

NOTE: On Adventure-models bolts M6x35 are used instead of the two
upper bolts M6x30.

SX, SXC

M6x30

M6x55

SC

LC4-E

M6x30

M6x55

M6x65

M6x95

M6x30/35

M6x30

M6x65

M6X55

640 LC4 2003 on

M6x55

M6x30

M6x55

M6x65

M6x30/35

6-6D

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

1

2

3

SXC/SMC 2003 on

M6x55

M6x30

M6x65

4

5

Mounting oil filter

– Fit oil filter with rubber gasket onto the connection in the oil filter

cover.

– Fit a new O-ring into the oil filter cover groove or use new gasket

and fix the oil filter cover with the 3 bolts, tighten bolts with 5 Nm.

Mounting the engine sprocket

– Lubricate O-ring (25x2 mm) with oil and slide over countershaft. 
– Slide distance bushing 

1 

in position so that O-ring is in correct

position.

NOTE: The distance bushing for Duke and Supermoto-models is 2mm
thicker.

! 

CAUTION

!

D

O NOT REVERSE DUST LIP OF THE SHAFT SEAL

.

– Fit the engine sprocket with the collar facing the housing.

NOTE: For Duke and Supermoto-models an additional 2 mm washer is
used.

– Apply Loctite 243 to thread of sprocket bolt.
– Mount spring retainer 

2

and sprocket bolt 

3

.

– Apply counterpressure with the sprocket holding spanner and tighten

sprocket bolt.

NOTE: Tighten bolts with quality 8.8 to 40 Nm, bolts with quality 10.9
to 60 Nm.

NOTE (from model 2003 on):
A collar nut 

4

and a lock washer 

5

are installed in some of the models

instead of a collar screw.

Tightening torque off the collar nut: 60 Nm

6-7D

Mount the timing gear and the timing chain

– Insert woodruff key for timing gear into crankshaft and fit timing

gear onto crankshaft with high collar towards housing.

– Fit timing chain onto timing gear and draw up through chain tunnel.

– Insert the timing chain guide 

1

, apply Loctite 243 to the Allen head

bolt 

2

and mount. 

– Apply Loctite 243 to the thread of the flat-head screw 

4

.

– Fasten timing chain tensioner 

3

with flat head screw.

– Check timing chain tensioner for smooth operation.

– Insert the safety device 

5

, apply Loctite 243 to the Allen head bolt

6

and mount.

Mounting the oil pumps

– Clean the sealing surfaces and install the oil pumps in the engine

housing (

A

M6x25!)

– Degrease the threads and use Loctite 243 to secure the bolts in their

position.

– Degrease the threads of both bolts 

7

, apply Loctite 243 and mount

the retaining bracket 

8

.

– Put the stop discs (8.1x15x0.5 mm) onto the oil pump shafts. 
– Insert the bearing needles into the oil pump shafts and slide on the

oil pump gears (high collars must face the casing; the small oil pump
gear must face the upper oil pump).

NOTE: From model 2002 onwards both oil pumps are fitted with the
same size of oil pump gear.

– Put on the upper stop discs 

9

(8.1x15x0.5 mm) and mount the

locking discs 

bk

.

1

2

3

4

5

6

7

8

9

10

A

6-8D

Repair manual  KTM LC4 

Art.-Nr

.  3.206.006 -E

Mounting the balancer shaft and the primary pinion

– Fit balancer shaft in the bearing.
– Mount woodruff key in crankshaft and place primary pinion on the

crankshaft. When doing so, adjust the teeth of the primary pinion
and the balancer shaft in such a way that the markings 

A

and 

B

coincide.

– Apply Loctite 243 to the crankshaft thread.
– Mount spring ring and hexagon nut and tighten hexagon nut to 170

Nm.

! 

CAUTION

!

I

F THE BALANCER SHAFT IS NOT INSTALLED ALSO REMOVE BOTH GROOVED BALL

BEARINGS

(

IN THE CLUTCH COVER AND IN THE ENGINE HOUSING

). O

THERWISE THE

GROOVED BALL BEARINGS WOULD DROP OUT OF THE BEARING SEATS AND CAUSE
ENGINE DAMAGE AS SOON AS THE ENGINE HEATS UP

.

Mounting the clutch

– Fit kickstarter intermediate gear 

1

onto counter shaft with clearance

space towards housing.

– Slide the inner ring and the needle bearing 

2

onto the main shaft.

– Fit outer clutch hub and outer stop disc 

3

(22.2x35x3 mm).

– Degrease the thread of the main shaft.
– Place inner clutch hub and a new safety plate on the main shaft.
– Coat the thread of the main shaft with Loctite 243 and mount

hexagon nut.

– Fit clutch holder and tighten hexagon nut to 100 Nm (60 ft.lb.).
– Remove clutch holder. 
– Check clutch hub and main shaft for smooth operation and axial 

clearance.

– Secure outer clutch hub hexagon nut by bending the safety plate up

into place.

A

B

1

2

3