KTM 50 SX 2010 User Manual

MOTORCYCLE 7
3.1Jacking up the motorcycle
700475-01
Note
Danger of damage The parked vehicle may roll away or fall over.
– Always place the vehicle on a firm and even surface.
– Jack up the motorcycle underneath the engine.
Work stand (54829055000) ( p. 145)
– Secure the motorcycle against falling over.
3.2Removing the motorcycle from the work stand
Note
Danger of damage The parked vehicle may roll away or fall over.
– Always place the vehicle on a firm and even surface.
– Remove the motorcycle from the work stand.
– Remove the work stand.
3.3Starting
Danger
Danger of poisoning Exhaust gases are poisonous and inhaling them may result in unconsciousness and/or death.
– When running the engine, always make sure there is sufficient ventilation, and do not start or run the engine in an enclosed
space without an effective exhaust extraction system.
Note
Engine failure High engine speeds in cold engines have a negative effect on the service life of the engine.
– Always warm up the engine at low engine speeds.
Info
If the motorcycle is unwilling to start, the cause can be old fuel in the float chamber. The flammable elements of the fuel
evaporate after a long time of standing.
If the float chamber is filled with fresh fuel, the engine starts immediately.
– Turn the knurled screw on the fuel tap all the way counterclockwise.
Fuel can flow from the fuel tank to the carburetor.
– Remove the motorcycle from the stand.
The engine is cold
(50 SX)
– Pull the choke knob fully out and turn it by max. ¼ turn.
(50 SX Mini)
– Push the choke lever up all the way.
– Forcefully step on the kickstarter, pushing it all the way forward.
Info
Do not open the throttle.

KTM 50 SX 2010 Specifications

General

Front Brake	Disc brake
Rear Brake	Disc brake
Cooling System	Liquid cooled
Fuel Tank Capacity	2.3 L
Starter	Kickstarter
Rear Brake Diameter	160 mm
Engine Type	Single-cylinder, 2-stroke
Displacement	49 cc
Bore x Stroke	39.5 mm x 40.0 mm
Rear Suspension	Monoshock
Frame	Steel

Summary

Motorcycle Operation

Starting the engine

Front Fork and Triple Clamp Service

Removing the fork legs

Step-by-step guide for safely removing the front fork legs from the motorcycle.

Checking the fork legs

Instructions for inspecting inner tubes, outer tubes, and springs for damage or wear.

Removing the lower triple clamp

Shock Absorber and Swingarm Service

Adjusting the rebound damping of the shock absorber

How to adjust the shock absorber's rebound damping for desired ride characteristics.

Adjusting the spring preload of the shock absorber

Steps to adjust the shock absorber spring preload for proper sag settings.

Servicing shock absorber

Air Filter Service

Front Wheel Service

Removing front wheel

Step-by-step instructions for safely removing the front wheel.

Installing the front wheel

Procedure for correctly installing the front wheel.

Rear Wheel Service

Removing rear wheel

Step-by-step guide for safely removing the rear wheel.

Installing the rear wheel

Procedure for correctly installing the rear wheel.

Cleaning the chain

Checking the chain tension

Adjusting chain tension

Brake System Service

Checking the front brake fluid level

Procedure for checking the front brake fluid reservoir level.

Checking the front brake linings

Inspection of front brake linings for wear and damage.

Checking the rear brake fluid level

Procedure for checking the rear brake fluid reservoir level.

Checking the rear brake linings

Inspection of rear brake linings for wear and damage.

Engine Service

Removing the engine

Step-by-step guide for safely removing the engine from the frame.

Installing the engine

Procedure for correctly installing the engine back into the frame.

Removing the cylinder head

Instructions for disassembling and removing the cylinder head.

Removing the piston

Procedure for removing the piston from the cylinder.

Installing the piston

Steps for correctly installing the piston into the cylinder.

Installing the cylinder

Procedure for fitting the cylinder onto the engine block.

Engine - Work on Individual Parts

Changing the conrod bearing

Procedure for replacing the conrod bearing.

Checking the crankshaft run-out on the bearing pin

Method for checking crankshaft run-out to ensure alignment.

Checking/measuring clutch

Engine - Assembly

Installing the crankshaft

Procedure for installing the crankshaft into the engine case.

Installing the left engine case

Steps for fitting the left section of the engine case.

Carburetor Service

Removing the carburetor (50 SX)

Instructions for safely removing the carburetor from the 50 SX model.

Installing the carburetor (50 SX)

Procedure for correctly installing the carburetor on the 50 SX.

Clutch Service

Removing the centrifugal force clutch

Step-by-step guide for disassembling the centrifugal clutch.

Checking clutch engagement speed

Procedure for measuring and verifying the clutch engagement speed.

Adjust the clutch engagement speed

Water Pump and Cooling System

Lubrication System Service

Ignition System Service

Checking the ignition system

Troubleshooting

Engine turns but does not start

Diagnosing causes and solutions when the engine fails to start.

Engine has no idle

Troubleshooting steps for an engine that does not maintain idle speed.

Engine overheats

Identifying and resolving issues causing the engine to overheat.

Technical Data - Engine

Capacity - gear oil

Technical Data - Carburetor

50 SX Carburetor Specifications

50 SX Mini Carburetor Specifications

Technical Data - Chassis

Technical Data - Fork

50 SX Fork Specifications

50 SX Mini Fork Specifications

Technical Data - Shock Absorber

50 SX Shock Absorber Specifications

50 SX Mini Shock Absorber Specifications

Service Schedule

Important maintenance work for authorized KTM workshop

List of maintenance tasks recommended for authorized KTM workshops.

Wiring Diagram

Wiring diagram

Substances

Special Tools