🏷️ Basic Information

Make:

KTM

Model:

SX, MXC, EXC Racing

Model Variants:

250, 400, 520, 525

Year Range:

2000, 2001, 2002, 2003, 2004

Manual Code Prefix:

Likely starts with '8000...'

👋 Introduction

Segment:

High-performance off-road motorcycles (Motocross, Enduro, Supercross)

Target Audience:

Professional racers, serious amateur riders, mechanics, and KTM enthusiasts.

Competitors:

Yamaha YZ, Honda CRF/CR, Suzuki RM/RM-Z, Kawasaki KX/KX-F.

Unique Selling Points:

KTM's reputation for powerful engines, advanced WP suspension, and robust build quality for demanding off-road use.

Manual Benefit:

Provides essential information for maintaining peak performance and longevity of these competitive machines.

Manual Accuracy:

OEM equivalent ensures factory-correct procedures and specifications.

📋 Manual Details

Primary Coverage:

Workshop Service Repair

Secondary Coverage:

Maintenance, Troubleshooting, Diagnostics, Rebuilds

Estimated Pages:

Likely 300-600 pages (typical for comprehensive service manuals)

Type:

Workshop Service Repair Manual

Language:

English

Format:

Downloadable PDF

📖 Manual Coverage

Engine:

Comprehensive engine disassembly, inspection, assembly, tuning, and repair for all listed displacements.

Cooling System:

Radiator, coolant flow, fan operation, thermostat, and related components.

Fuel System:

Carburetor(s) (Mikuni VM series likely), fuel pump, fuel lines, fuel tank inspection and cleaning.

Ignition System:

CDI unit, spark plug, ignition coil, wiring, timing specifications.

Transmission:

Clutch operation, gearbox disassembly, inspection, assembly, gear selection, and lubrication.

Suspension:

Front forks (WP USD likely) - disassembly, seal replacement, oil levels and types, damping adjustments. Rear shock absorber - servicing, spring preload, damping adjustments.

Brakes:

Hydraulic brake systems (front and rear), caliper service, pad replacement, fluid type (DOT 4 likely), bleeding procedures.

Electrical System:

Wiring diagrams, battery maintenance, lighting, starter motor, charging system, fuses, switches.

Chassis:

Frame inspection, steering head bearing service, wheel bearing replacement, spoke tensioning.

Bodywork:

Fairing removal and installation, seat, fuel tank cover, fenders.

Scheduled Maintenance:

Oil changes, filter replacements, chain lubrication and adjustment, spark plug checks, valve clearance adjustments.

Troubleshooting:

Diagnostic charts for common problems, symptom-based troubleshooting guides.

Engine Repair:

Top-end rebuilds (piston, rings, cylinder), bottom-end rebuilds (crankshaft, bearings), timing chain replacement.

Transmission Repair:

Gearbox disassembly and reassembly, clutch plate replacement.

Suspension Servicing:

Fork seal replacement, fork oil change, rear shock absorber rebuild.

Brake System Maintenance:

Brake bleeding, caliper piston service, fluid replacement.

Electrical Diagnostics:

Wiring harness troubleshooting, component testing.

Depth:

Comprehensive, suitable for professional mechanics and experienced DIY enthusiasts.

Diagnostic Level:

Includes detailed diagnostic flowcharts and component testing procedures.

Rebuild Level:

Covers complete engine and transmission rebuilds, including specifications and torque values.

📊 Manual Specifications

File Type:

PDF

Searchability:

Likely text-searchable PDF, allowing quick access to information.

Image Resolution:

Expect clear diagrams and high-resolution images suitable for printing.

Binding:

N/A (Digital PDF)

Paper Quality:

N/A (Digital PDF)

⚙️ Engine Specifications

Configuration:

Single-cylinder, four-stroke (typically SOHC or DOHC depending on specific model year and variant).

Displacement 250:

250cc (Approximate)

Displacement 400:

400cc (Approximate)

Displacement 520:

520cc (Approximate)

Displacement 525:

525cc (Approximate)

Cooling:

Liquid-cooled

Starting System:

Kick-start (likely primary, some models might have electric start option but less common for this era SX/MXC).

Horsepower 250:

Estimated 35-45 HP (Varies by model and tuning)

Horsepower 525:

Estimated 50-60 HP (Varies by model and tuning)

Torque Curve:

Broad and torquey, characteristic of KTM's off-road focused engines.

Carburetor Type:

Mikuni VM Series (e.g., VM38 or VM40 likely for larger displacements).

Fuel Type:

Unleaded gasoline (Octane rating specified in manual, typically 91+).

Engine Oil Type:

High-quality motorcycle-specific 4-stroke engine oil (e.g., Motorex or equivalent, SAE 10W/40 or 15W/50 depending on temperature).

Engine Oil Capacity:

Approximately 0.8 - 1.2 liters (refer to manual for exact capacity by model).

Coolant Type:

Ethylene glycol-based coolant (50/50 mix with distilled water recommended).

🔧 Transmission

Type:

Constant mesh, sequential manual gearbox.

Number Of Gears:

Typically 5 or 6 speeds (manual will specify for each model variant).

Optional Features:

N/A (These were performance-oriented, typically no automatic options).

Clutch Type:

Wet multi-plate clutch, hydraulically operated.

Transmission Oil Type:

Often shared with engine oil (JASO MA rated) or separate transmission oil specified.

📐 Dimensions

Wheelbase:

Varies by model, but typically around 57-58 inches (1450-1475 mm).

Seat Height:

High seat height typical of off-road bikes, around 37-39 inches (940-990 mm).

Dry Weight:

Approx. 230-255 lbs (105-115 kg) depending on engine size and model variant.

🛡️ Safety Features

Crash Test Results:

N/A (Motorcycles are not typically subjected to standardized crash testing like cars).

Braking System:

Powerful hydraulic disc brakes front and rear for superior stopping power.

Frame Construction:

Chromoly steel trellis frame providing strength and rigidity for off-road abuse.

💡 Technology Features

Infotainment Features:

N/A (These are competition motorcycles designed for performance, not comfort or entertainment features).

Assistance Features:

N/A (No electronic rider aids like ABS or traction control are present on these models).

Connectivity Features:

N/A

🔧 Maintenance

Oil Change:

Every 15-30 hours of riding or annually (refer to manual for precise recommendations based on usage).

Air Filter Cleaning:

Frequent checks and cleaning are crucial, especially in dusty conditions (every few rides recommended).

Valve Clearance Check:

Every 30-60 hours of riding or annually.

Chain And Sprockets:

Regular cleaning, lubrication, and adjustment are vital for performance and longevity.

Brake Fluid Type:

DOT 4 recommended. Never mix DOT 3 and DOT 4. Always use fresh fluid.

Fork Oil Type:

Specific WP suspension oil (e.g., WP Fork Oil 5W or equivalent). Manual will detail weight and quantity.

Common Wear Items:

Clutch plates, wheel bearings, steering head bearings, fork seals, piston rings due to demanding off-road use.

Carburetor Tuning:

May require jetting adjustments based on altitude, temperature, and exhaust modifications.

Cooling System Maintenance:

Regularly check coolant levels and hose condition to prevent overheating.

📚 Vehicle History

Brand Focus:

KTM is renowned for its off-road racing heritage and 'Ready to Race' philosophy.

Development Period:

These models represent a significant evolution in KTM's off-road performance, building on earlier generations.

Manufacturing Location:

Austria (KTM AG headquarters).

Sales Figures:

Difficult to ascertain specific sales figures for these performance models, but KTM has consistently been a strong performer in the off-road segment.

🏆 Awards & Recognition

Racing Success:

KTM models of this era were highly successful in professional motocross and enduro racing, contributing to their reputation and desirability.

Motocross Magazine Reviews:

Generally received excellent reviews for power, suspension, and handling from off-road publications of the time.