KTM LC4 400-660LC42003 engine. Manual - part 31
10-45D
Repair manual KTM LC4
Art.-Nr
. 3.206.006 -E
Engine
400 SXC
Design
Liquid-cooled single cylinder 4-stroke engine
Displacement
398 ccm
Bore / Stroke
89 / 64 mm
Ratio
10,8 : 1
Fuel
unleaded premium gasoline with a least RON 95
Valve timing
4 valves over rocker arm and 1 overhead camshaft, camshaft drive through single chain
Camshaft
249/1
Valve timing by 1 mm
IO 22° BTDC EO 60° BBDC
valve clearence
IC 42° ABDC EC 4° ATDC
Valve diameter
Intake: 36 mm Exhaust: 30 mm
Valve clearence cold
Intake: 0,20 mm Exhaust: 0,20 mm
Crank shaft bearing
2 cylinder roller bearing
Connecting rod bearing
needle bearing
Top end bearing
bronze bushing
Piston
cast aluminium alloy
Piston rings
1 compression ring, 1 taper face ring, 1 oil scraper ring
Engine lubrication
forced-feed lubrication through Eaton-Oilpump with oil sump
Engine oil
see bellow
Engine oil quantity
1,45 liters (0,38 US gallons)
Primary ratio
straight geared spur wheels 30 : 81 teeth
Clutch
multi disc clutch in oil bath
Transmission
5-speed claw shifted
Gear ratio
1st 14:35
2nd 15:24
3rd 18:21
4th 20:19
5th 22:18
Ignition system
contactless thyristor ignition with electronic advanced system type SEM
Ignition timing
adjustment to max. 38 ° BTDC at 6000 rpm
Generator
12V 130W
Spark plug
NGK D8EA
Spark plug gap
0,6 mm
Cooling system
liquid cooled, permanent rotation of cooling liquid through mechanic driven water pump
Cooling liquid
1 liter, 40% antifreeze, 60% water, at least –25°C (–13°F)
Starting equipment
decompressor automatic and hand actuated, cold and hot start knob on carburetor
TECHNICAL SPECIFICATIONS – ENGINE 400 SXC USA 2000
Crank shaft
axial play..................................................0,03 - 0,12 mm
(0,001-0,005 in)
run out of crank stud .................................max. 0,08 mm
(0,003 in)
Connecting rod bearing
radial play ..................................................max. 0,05 mm
(0,002 in)
axial play ...................................................max. 1,00 mm
(0,04 in)
Piston cast
assembly clearance ...................................max. 0,05 mm
(0,002 in)
Piston rings end gap
compression rings ......................................max. 0,60 mm
(0,023 in)
oil scraper ring ...........................................max. 0,80 mm
(0,031 in)
Valves
seat sealing intake......................................max. 1,50 mm
0,059 in)
seat sealing exhaust ...................................max. 2,00 mm
(0,080 in)
run out of valve heads ...............................max. 0,03 mm
(0,001 in)
valve guides diameter ................................max. 7,05 mm
(0,277 in)
Oil pump
clearance outer rotor - housing..................max. 0,20 mm
(0,008 in)
clearance outer rotor - inner rotor..............max. 0,20 mm
(0,008 in)
Bypaß valve
minimum spring lenght..........................................25 mm
(1 in)
Clutch discs
wear limit organic .................................................2,5 mm
(0,1 in)
Clutch springs
minimum lenght ...........................34,5 mm (new 37 mm)
(1,36 in - new 1,45 in)
Transmission shafts
axial play......................................................0,1 - 0,4 mm
(0,004 - 0,016 in)
ASSEMBLY CLEARANCE, WEAR LIMIT