KTM 450 SX 2004 User Manual (English)

Questions and Answers:

D
David ParksAug 19, 2025
How to fix KTM 450 SX 2004 engine when it doesn’t crank?
- J
  James ElliottAug 20, 2025
  If the engine of your KTM Motorcycle doesn’t crank, it could be due to an operating error, a blown fuse, a discharged battery, or low outside temperature. You should turn on the emergency-OFF switch (Australia only), dismount the left paneling and the filter box cover and replace the fuse in the starter relay, recharge the battery and investigate the causes for discharging, or start the engine with the kickstarter.
A
Alyssa WilkinsonAug 22, 2025
Why does my KTM 450 SX 2004 engine get too hot?
- B
  Billy DeleonAug 23, 2025
  If the engine of your KTM Motorcycle gets too hot, it could be due to several reasons. You may have insufficient cooling liquid, so you should refill it and check for leaks. There might not be enough air stream, so you should drive briskly. Another reason may be that the cooling system hasn't been bled, so you should bleed it. The radiators may be very dirty, so you should clean them with a water jet. There could be foam formation in the cooling system, so you should replace the cooling liquid and use antifreeze liquid with a brand name. A cooling hose might be bent, so you should shorten or replace it. Finally, the thermostat may be defective, so you should dismount and check it, or replace it.
T
Thomas RobinsonAug 26, 2025
What to do if my KTM Motorcycle engine will not reach full power?
- L
  Lauren NguyenAug 26, 2025
  If your KTM Motorcycle engine will not reach full power, the fuel supply might be partially interrupted, or the carburetor could be dirty, so you should clean and check the fuel system and carburetor. The float may be leaking, so you should replace it. The air filter might be very dirty, so you should clean or replace it. The exhaust system may not be tight or is deformed, or the silencer may not contain enough glass fiber yarn, so you should check if the exhaust is damaged and replace the glass fiber yarn in the exhaust silencer. The valve gap might be too small, so you should adjust it. Finally, the electronic ignition timing may be faulty, so you should have it checked.
L
Lawrence SchmidtAug 28, 2025
Why KTM Motorcycle engine fails to idle?
- I
  ibowenAug 28, 2025
  If your KTM Motorcycle engine fails to idle, it may be due to a clogged idling jet, so you should disassemble the carburetor and clean the jets. It could also be due to an incorrect adjustment of adjusting screws on the carburetor, so you should have the carburetor adjusted. A defective spark plug or ignition system may also be the cause, so you should replace the spark plug or have the ignition system checked.
M
Megan HartAug 30, 2025
What to do if KTM Motorcycle engine stops or splutters in carburetor?
- M
  Maria RamirezAug 30, 2025
  If your KTM Motorcycle engine stops or sputters in the carburetor, it could be due to insufficient fuel or the engine taking air out of control. To fix this, clean and check the fuel system and carburetor, and check the rubber sleeve and carburetor for a tight fit.
T
Timothy GreenSep 2, 2025
Why KTM Motorcycle engine does not rev high?
- J
  Jacob MoyerSep 3, 2025
  If your KTM Motorcycle engine does not rev high, it may be because the carburetor fuel level is too high due to a dirty or worn float needle valve, so you should dismount the carburetor and check if it's worn out. The carburetor jets might be loose, so you should tighten them. Finally, the electronic ignition timing could be faulty, so you should have the ignition system checked.
J
Jacob RobertsonSep 5, 2025
Why is there high oil consumption in my KTM Motorcycle?
- M
  Mr. Scott Lee MDSep 5, 2025
  If you observe high oil consumption in your KTM Motorcycle, it could be because the hose of the engine ventilation is bent, so you should dislocate or replace it with a non-buckling ventilation hose. Another reason could be that the engine oil level is too high, so you should check and correct it if necessary. Lastly, the motor oil might be too thin (viscosity), so consider using thicker engine oil.
S
Sandra RogersSep 8, 2025
What causes all lamps to blow out on my KTM Motorcycle?
- A
  Amanda WeaverSep 8, 2025
  If all switched-on lamps in your KTM Motorcycle have blown out, it is likely that the capacitor or voltage regulator is faulty. You should dismount the seat and fuel tank and check the connections, and then have the capacitor and voltage regulator checked.

KTM 450 SX 2004 Specifications

General

Engine type	Single-cylinder, 4-stroke
Displacement	449 cc
Compression ratio	12.5:1
Cooling system	Liquid cooled
Ignition	Kokusan digital
Transmission	5-speed
Front suspension	WP USD 48 mm
Front brakes	Single 260mm disc
Rear brakes	Single 220mm disc
Fuel capacity	7.5 liters
Starter	Kickstarter
Seat height	925 mm
Bore x Stroke	95.0 mm x 63.4 mm
Fuel system	Carburetor
Rear suspension	WP shock absorber

Summary

Important Safety Warnings

WARNING: Endangering Body and Life

Instructions that endanger your body and life if ignored.

CAUTION: Damage to Motorcycle

Instructions that could cause damage to motorcycle parts.

Introduction and Owner's Advice

Familiarizing with Your New Motorcycle

Read manual carefully to understand operation and characteristics.

Importance of KTM-Approved Parts

Use only KTM-approved parts for safety and to avoid damage.

Responsible Riding Practices

Ride responsibly, be environmentally conscious, and respect others' rights.

Warranty and Model Usage Guidelines

Limited Warranty Information

Details on warranty coverage and prerequisites like service.

Model-Specific Usage Restrictions

Guidelines for SX/SXS, MXC, and EXC models regarding public roads.

Serial Number Identification

Chassis Number Location

Location of the chassis number stamped on the steering head tube.

Engine Number and Type Location

Location of the engine number and type stamped on the engine.

Operation Instruments - Levers

Clutch Lever Operation

Location and adjustment of the clutch lever.

Hand Decompression Lever Function

Use of the hand decompression lever for starting.

Hand Brake Lever Operation

Location and adjustment of the hand brake lever.

Operation Instruments - Switches

Short Circuit and Combination Switches

Function of the short circuit and combination switches.

Headlamp and Flasher Switches

Operation of headlamp and flasher switches.

Starter Button Function

How to use the starter button.

Digital Speedometer and Indicator Lamps

Indicator Lamps Function

Meaning of the green and blue control lamps.

Electronic Speedometer Operation

Activation and basic functions of the electronic speedometer.

Tripmaster Display Modes (Part 1)

SPEED/ODO and SPEED/MAX Display Modes

Using the SPEED/ODO and SPEED/MAX display modes.

SPEED/LAP and LAP/LAP Display Modes

Using the SPEED/LAP and LAP/LAP display modes.

Tripmaster Display Modes (Part 2)

SPEED/CLK and SPEED/H Modes

Displaying time and operating hours.

SPEED/TRP1, SPEED/AVS1, SPEED/STP1 Modes

Displaying trip, average speed, and stop watch data.

Tripmaster Display Modes (Part 3)

SPEED/TRP2, SPEED/AVS2, SPEED/STP2 Modes

Using trip 2, average speed 2, and stop watch 2.

Setting the Clock

Procedure to set the digital clock on the speedometer.

Managing Display Modes

How to activate or deactivate display modes.

Tripmaster Settings and Overview

Changing Units (Km/Miles)

How to change the units from kilometers to miles and vice versa.

Tripmaster Function Overview

Summary table of Tripmaster switch functions.

Fuel and Emergency Controls

Emergency OFF Switch Operation

Function and use of the emergency OFF switch.

Fuel Tap and Choke Operation

How to operate the fuel tap and choke for starting.

Engine Starting and Rider Controls

Hot Start Device Function

Use of the hot start device for starting a warm engine.

Shift Lever and Kickstarter Operation

How to operate the shift lever and kickstarter.

Foot Brake Pedal and Side Stand

Location and use of the foot brake pedal and side stand.

Front and Rear Suspension Damping

Fork Damping Adjustments

Adjusting compression and rebound damping on the front fork.

Shock Absorber Damping Adjustments (SX)

Adjusting damping on SX model shock absorbers.

Steering Lock and Shock Absorber Damping

Steering Lock Mechanism

How to use the steering lock for securing the motorcycle.

Shock Absorber Damping (MXC/EXC)

Adjusting damping on MXC/EXC model shock absorbers.

General Riding and Safety Tips

Initial Operation and Running-In

Instructions for initial operation and running-in racing models.

General Riding Warnings

Important safety warnings for riding the motorcycle.

Pre-Ride Checks and Starting Procedures

Before Each Start Checks

Essential checks to perform before starting the motorcycle.

Starting Procedures (Cold/Warm Engine)

How to start the engine when cold or warm.

Driving Techniques and Engine Starting Issues

Engine Starting and Flooded Engine

Procedures for starting cold/warm engines and handling a flooded engine.

Starting Off and Shifting Gears

How to start moving and shift gears smoothly.

Braking, Stopping, Fueling, and Warnings

Braking Techniques and Warnings

Proper braking techniques and related safety warnings.

Stopping, Parking, and Fueling Precautions

Safe procedures for stopping, parking, and fueling the motorcycle.

Periodic Maintenance Schedule

Maintenance Tasks at 3-Hour Service

Maintenance tasks required after 3 hours of use or 20 liters of fuel.

Maintenance Tasks at 15-Hour Service

Maintenance tasks required after 15 hours of use or 100 liters of fuel.

Recommended Maintenance by Extra Order

Additional maintenance tasks recommended to be done by a KTM workshop.

Rider Maintenance Checks

Pre-Ride and Cleaning Maintenance

Daily checks and maintenance after cleaning.

Cross-Country Use Maintenance

Specific maintenance for cross-country riding.

Workshop Engine Inspection (Enduro Competitions)

15 to 135 Hour/Liter Engine Inspections

Inspection schedule for engine components up to 135 hours/900 liters.

Workshop Engine Inspection (Hobby Enduro)

30 to 270 Hour/Liter Engine Inspections

Inspection schedule for engine components up to 270 hours/1800 liters.

Chassis and Engine Maintenance

Steering Head Bearing Adjustment

How to check and adjust the steering head bearing for play.

Front Fork Maintenance

Front Fork Breather Plug Check

Procedure for relieving pressure from the front fork.

Cleaning Fork Dust Sleeves

How to clean the dust protection bellows of the telescopic fork.

Suspension Setup by Rider Weight

Basic Suspension Setup for Rider Weight

Adjusting suspension components based on rider's weight.

Adjusting Front Fork Spring Preload (SX)

How to adjust the spring preload on SX model forks.

Shock Absorber and Spring Setup

Checking Shock Absorber and Spring Suitability

Checking shock absorber suitability using riding sag.

Determining Static Sag

Procedure to measure static sag of the shock absorber.

Determining Riding Sag

Procedure to measure riding sag of the shock absorber.

Fork Spring and Preload Adjustment

Replacing Fork Springs

Guidance on replacing fork springs based on rider weight.

Adjusting Telescopic Fork Spring Preload

How to adjust spring preload on SX, MXC/EXC forks.

Handlebar and Shock Adjustments

Handlebar Position Adjustment

How to adjust the handlebar position for comfort.

Shock Absorber Spring Preload Adjustment

Procedure to change shock absorber spring preload.

Pivot Bearing Maintenance

Information on pivot bearing lubrication and cleaning.

Chain Tension and Maintenance

Checking Chain Tension

How to check the correct chain tension and slack.

Correcting Chain Tension

Procedure for adjusting chain tension and alignment.

Chain Care and Wear

Chain Maintenance Procedures

How to clean and lubricate the chain for longevity.

Checking Chain Wear

How to measure chain wear and when to replace it.

KTM Disc Brake System Overview

Brake Caliper and Pad Information

Details on brake calipers, pads, and their types.

Brake Disc Wear Limits

Information on brake disc wear limits and safety.

Brake Fluid Reservoir and Fluid Type

Checking brake fluid level and recommended fluid types.

Front Brake System Maintenance

Adjusting Front Brake Lever Free Travel

How to adjust the free travel of the hand brake lever.

Checking and Refilling Front Brake Fluid

Checking fluid level and refilling the front brake fluid reservoir.

Brake Pad and Rear Brake Maintenance

Checking and Replacing Front Brake Pads

How to inspect and replace front brake pads.

Adjusting Foot Brake Pedal Position

Adjusting the basic position of the foot brake pedal.

Checking Rear Brake Fluid Level

Checking the brake fluid level for the rear brake.

Rear Brake System Maintenance

Refilling Rear Brake Fluid Reservoir

How to refill the rear brake fluid reservoir.

Checking and Replacing Rear Brake Pads

How to inspect and replace rear brake pads.

Wheel Removal and Installation

Front Wheel Removal and Installation

Procedure for removing and installing the front wheel.

Rear Wheel Removal and Installation

Procedure for removing and installing the rear wheel.

Wheel Spoke Tension

Checking Spoke Tension

How to check spoke tension for wheel stability.

Tires and Air Pressure

Tire Pressure Recommendations

Recommended air pressure for off-road and road driving.

Speedometer and Battery Maintenance

Magnetic Sensor Adjustment

Setting the correct distance for the magnetic speed sensor.

Replacing Speedometer Battery

Procedure for replacing the digital speedometer battery.

Battery Maintenance and Charging

Battery Care and Removal

How to care for, remove, and install the battery.

Battery Charging Procedures

Guidelines for charging the motorcycle battery.

Electrical System Components

Fuse Replacement

Location and replacement of the fuse.

Headlight and Parking Light Bulb Replacement

How to replace headlight and parking light bulbs.

Cooling System Maintenance

Cooling System Operation and Checks

Information on coolant, checking levels, and bleeding.

Exhaust System Maintenance

Silencer Packing Replacement

How to replace the glassfiber yarn packing in the silencer.

Spark Arrester Cleaning

Procedure for cleaning the spark arrester.

Air Filter and Cable Adjustments

Air Filter Cleaning Procedure

How to clean and maintain the air filter.

Decompression Cable and Throttle Cable Adjustment

Adjusting the hand decompression and throttle cables.

Hydraulic Clutch Maintenance

Clutch Lever Position Adjustment

How to adjust the original position of the clutch lever.

Hydraulic Clutch Oil Level and Bleeding

Checking oil level and bleeding the hydraulic clutch system.

Carburetor Adjustment and Checks

Carburetor Idle Speed Adjustment

How to adjust the carburetor idling speed and mixture.

Checking Carburetor Float Level

Procedure to check the float level in the carburetor.

Carburetor and Engine Oil Maintenance

Draining Carburetor Float Chamber

How to drain the carburetor float chamber after cleaning.

Engine Oil Level Check

How to check the engine oil level correctly.

Engine Oil Service

Engine Oil Specifications

Recommended engine oil types and viscosity.

Changing Engine Oil and Filters

Procedure for changing engine oil and oil filters.

Cleaning and Storage Procedures

Motorcycle Cleaning Guidelines

How to properly clean the motorcycle.

Winter Storage Preparation

Steps for preparing the motorcycle for long-term storage.

Technical Data - Engine Specifications

Engine Type and Displacement

Details on engine type, displacement, bore, and stroke.

Valve Train and Lubrication Data

Information on valve timing, camshafts, and lubrication.

Transmission and Ignition System Data

Specifications for transmission, gears, and ignition system.

Carburetor Settings

Carburetor Settings for 250/450 Models

Carburetor settings for 250/450 EXC and 450 SX models.

Carburetor Settings for 525 Models

Carburetor settings for 525 EXC, MXC, and SX models.

Tightening Torque Specifications

Chassis Component Torque Settings

Torque specifications for chassis fasteners.

Engine Component Torque Settings

Torque specifications for engine fasteners.

Technical Data - Chassis Specifications

Frame, Fork, and Suspension Data

Specifications for frame, fork, and rear suspension.

Brake, Wheel, and Tire Data

Specifications for brakes, wheels, and tires.

Chassis Adjustment Torque Settings

Torque values for chassis adjustments and components.

Related product manuals

KTM 450 SX RACING 2006

KTM 450 SX 2004 User Manual

Table of Contents