🏷️ Basic Information

Make:

KTM

Model:

250 SX, 400 SX, 450 SX, 525 SX, 250 EXC, 400 EXC, 450 EXC, 525 EXC

Model Code Range:

SX series (Motocross), EXC series (Enduro)

👋 Introduction

Target Audience:

Owners, mechanics, and enthusiasts of KTM SX and EXC models from 2000-2007 for maintenance, repair, and restoration.

Value Proposition:

Provides essential technical data and repair procedures necessary for maintaining and servicing these high-performance off-road motorcycles, saving significant costs compared to professional dealer service.

Content Focus:

Detailed step-by-step instructions, exploded views, diagrams, torque values, and diagnostic charts.

📋 Manual Details

Years Covered:

2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007

Estimated Page Count:

Comprehensive (typical workshop manual for this era and range of models is 400-600+ pages, actual may vary based on specific printing/digitalization).

Manual Type:

Complete Workshop Service Repair Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine Systems:

Engine disassembly, assembly, overhaul, top end (cylinder, piston, valves), bottom end (crankshaft, connecting rod, bearings), cooling system (radiator, fan, coolant), lubrication system (oil pump, oil filter, oil passages).

Transmission Drivetrain:

Gearbox inspection, disassembly, assembly, shift mechanism, clutch (hydraulic or cable), primary drive, chain drive, sprockets.

Fuel System:

Carburetor (jetting, float bowl, needle, idle speed), fuel pump (if applicable for later models or specific variants), fuel tank, fuel lines, filters.

Ignition Electrical:

Ignition system (CDI, stator, coil), lighting system (if applicable to EXC models), battery, wiring diagrams, starter motor, troubleshooting electrical faults.

Suspension Chassis:

Front suspension (forks - disassembly, seals, oil level, valving, spring replacement), rear suspension (shock absorber - rebuild, damping adjustments, linkage system), swingarm, bearings.

Brakes:

Front and rear brake systems (calipers, master cylinders, brake lines, pads, rotors), bleeding procedure, hydraulic system troubleshooting.

Wheels Tires:

Wheel bearing inspection and replacement, spoke tension, tire mounting, rim maintenance.

Bodywork Frame:

Frame inspection, seat, fuel tank removal/installation, plastics, handlebars, controls.

Maintenance Tasks:

Routine maintenance checks, oil changes, filter replacements, spark plug service, chain adjustment, air filter cleaning/replacement, valve clearance checks.

Troubleshooting:

Diagnostic procedures for common problems, symptom-based troubleshooting guides, electrical fault finding.

Repair Procedures:

Detailed step-by-step instructions for component disassembly, repair, and reassembly for all major systems.

Technical Data Specs:

Torque specifications for all fasteners, fluid capacities, engine timing, electrical resistance values, dimensional data.

Depth Of Coverage:

Comprehensive rebuilds, advanced diagnostics, detailed component overhauls, troubleshooting of complex issues.

📊 Manual Specifications

File Format:

PDF

Resolution:

High-resolution scans (typically 300 dpi or higher for clarity).

Searchability:

Likely text-searchable PDF if OCR was performed, otherwise image-based.

Binding Type:

N/A (Digital Download)

Paper Type:

N/A (Digital Download)

⚙️ Engine Specifications

Engine Type:

Four-stroke, single-cylinder (LC4 engine family for most, though specific iterations vary)

Displacement Options:

Approximately 250cc, 400cc, 450cc, 525cc (exact CC may vary slightly by year and specific sub-model).

Cooling System:

Liquid-cooled

Horsepower Range:

Varies by displacement; e.g., 250s typically 30-40 HP, 525s 45-55+ HP (peak figures).

Torque Range:

Varies by displacement; e.g., 250s 20-25 lb-ft, 525s 35-45+ lb-ft.

Fuel Delivery:

Carbureted (e.g., Keihin, Mikuni models depending on year/variant)

Recommended Fuel:

Unleaded gasoline, octane rating as specified by KTM (typically 91 RON or higher).

🔧 Transmission

Transmission Type:

6-speed manual gearbox

Clutch Type:

Hydraulic actuated wet multi-plate clutch

Final Drive:

Chain drive

📐 Dimensions

Wheelbase:

Varies by model, typically around 1470-1500 mm (57.9-59.1 inches).

Dry Weight:

Varies by model and year, generally between 105-120 kg (231-265 lbs).

🛡️ Safety Features

Crash Test Ratings:

N/A (Off-road motorcycles are not subject to standard automotive crash testing.

Braking System:

Hydraulic disc brakes front and rear.

Frame Construction:

Chromium-molybdenum steel trellis frame.

💡 Technology Features

Features:

Basic motorcycle instrumentation (speedometer, tachometer, odometer, hour meter). No advanced infotainment systems.

Features:

None (Focus is on pure off-road performance).

Features:

N/A

🔧 Maintenance

Oil Change Interval:

Typically every 10-15 hours of riding or annually, depending on usage severity and model year recommendations.

Air Filter Cleaning:

Every 5-10 hours of riding or after dusty conditions.

Valve Clearance Check:

Typically every 20-30 hours of riding for competition use, or as specified in the manual.

Engine Oil Type:

KTM recommends specific motorcycle oils (e.g., Motorex Power Synt SAE 10W/40 or equivalent JASO MA certified synthetic oil).

Engine Oil Capacity:

Varies by model, typically around 1.0-1.3 liters.

Fork Oil Type:

KTM recommends specific suspension fluids (e.g., WP Suspension Fluid or SAE 5W/7.5W fork oil).

Fork Oil Level:

Specific to each fork model, e.g., 100-120 mm from the top of the stanchion with the spring removed and fork compressed.

Coolant Type:

Ethylene glycol based antifreeze/coolant mixture (50/50).

Common Wear Items:

Clutch wear, piston and ring wear, valve stem seals, wheel bearings, steering head bearings, linkage bearings, fork seals.

Engine Specific Considerations:

LC4 engines can be sensitive to oil level and maintenance intervals; early models may have had cam chain tensioner issues. Check for specific service bulletins.

Electrical Considerations:

Stator output and rectifier/regulator performance can be points of failure; ensure proper voltage regulation.

📚 Vehicle History

Manufacturer:

KTM AG, an Austrian manufacturer known for its off-road motorcycles.

Development Context:

These models represent a significant period of KTM's dominance in motocross (SX) and enduro (EXC) racing, featuring continuous refinements to their potent LC4 engine platform and chassis.

Production Period:

2000-2007 for the covered models and range.

🏆 Awards & Recognition

Racing Success:

KTM SX and EXC models from this era have a formidable racing pedigree, achieving numerous championships in Motocross and Off-Road racing disciplines worldwide.

Industry Reputation:

Highly regarded for performance, durability (when properly maintained), and off-road capability.