🏷️ Basic Information

Make:

KTM

Model:

450 SX ATV

Model Generation:

First Generation (LC4 Engine)

Years Covered:

2009, 2010, 2011

Chassis Codes:

Not explicitly stated in product info, but typically associated with specific chassis designations for KTM ATVs of this era.

Engine Codes:

LC4 (Liquid-cooled, Single-cylinder, Four-stroke)

👋 Introduction

Vehicle Segment:

Performance/Competition ATV

Target Audience:

Motocross and off-road racing enthusiasts, recreational riders seeking a powerful and capable machine.

Key Competitors Era:

Yamaha YFZ450, Honda TRX450R, Suzuki LT-R450 Quadracer.

Engine Type:

Powerful LC4 single-cylinder engine known for strong torque and broad powerband.

Suspension Platform:

Performance-oriented suspension designed for rough terrain and jumps.

Handling Characteristics:

Agile and responsive handling, typical of KTM's off-road focused design philosophy.

Manual Value Proposition:

Provides comprehensive, factory-level repair and maintenance information essential for owners and technicians.

📋 Manual Details

Manual Type:

Service Repair Workshop Manual

Language:

English

Format:

PDF Download

Intended User:

Professional Mechanics and Advanced DIY Enthusiasts

Estimated Page Count:

High (typical for comprehensive workshop manuals, likely exceeding 400 pages)

📖 Manual Coverage

Engine Overhaul:

Complete engine disassembly, inspection, repair, and reassembly procedures.

Fuel System:

Carburetor (likely Keihin FCR MX) tuning, cleaning, and repair; fuel pump, fuel tank, and lines.

Ignition System:

Ignition coil, CDI unit, spark plug, wiring diagnostics.

Cooling System:

Radiator, coolant lines, water pump, thermostat operation and maintenance.

Transmission:

Gearbox disassembly, inspection, repair, clutch operation and adjustment.

Drivetrain:

Chain and sprockets, rear axle assembly, wheel bearings.

Suspension Front:

USD (Upside Down) forks: disassembly, seal replacement, oil changes, valving adjustments, and spring replacement.

Suspension Rear:

Monoshock rear suspension: linkage, shock absorber rebuild, adjustment, and pivot bearing service.

Brakes Front:

Hydraulic disc brakes: caliper overhaul, pad replacement, rotor inspection, brake line bleeding.

Brakes Rear:

Hydraulic disc brakes: caliper overhaul, pad replacement, rotor inspection, brake line bleeding.

Steering:

Handlebar, steering stem, steering bearings, front hub assembly.

Electrical System:

Wiring diagrams, battery, lighting, starter motor, switches, fuses, and fault diagnosis.

Chassis Frame:

Frame inspection, swingarm service, footpeg mounts.

Bodywork:

Plastics, seat, fenders, fuel tank removal and installation.

Routine Maintenance:

Oil changes, filter replacements, chain adjustment, lubrication points.

Troubleshooting:

Diagnostic procedures for common performance issues and component failures.

Component Rebuild:

Detailed steps for rebuilding the engine, carburetor, suspension, and brake calipers.

Electrical Diagnostics:

Step-by-step fault finding using wiring diagrams and diagnostic charts.

Torquing Specifications:

Precise torque values for all critical fasteners.

Wheel Alignment:

Guidance on ensuring proper wheel alignment and balance.

Specification Tables:

Comprehensive tables of technical specifications and tolerances.

Depth Level:

In-depth, covering full disassembly, repair, and reassembly, including internal component specifications.

Diagnostic Capability:

Advanced diagnostics for engine performance, electrical systems, and mechanical components.

Special Tool Requirements:

Identification and usage instructions for specialized tools needed for certain procedures.

📊 Manual Specifications

File Type:

PDF

Searchability:

Likely text-searchable (standard for professionally produced PDF manuals).

Image Resolution:

High-resolution diagrams and photographs for clarity.

Binding Method:

N/A (Digital Download - PDF)

Paper Quality:

N/A (Digital Download - PDF)

⚙️ Engine Specifications

Engine Type:

LC4, Liquid-cooled, Single-cylinder, 4-stroke

Displacement:

Approximately 449.3 cc (bore and stroke specific, exact figures usually found in manual)

Bore X Stroke:

Not specified in product info, but typically around 95.0 mm x 63.4 mm.

Compression Ratio:

Likely around 11.5:1 or higher for performance.

Valve Train:

SOHC (Single Overhead Camshaft), 4 valves

Cooling Method:

Liquid-cooled

Horsepower:

Estimated 45-50 HP (at crankshaft, unconfirmed without manual data).

Torque:

Strong low-to-mid range torque, characteristic of LC4 engines.

Carburetor Type:

Keihin FCR MX 40mm (common for this model and era).

Fuel Type:

Unleaded gasoline, typically 90-95 octane (RON+MON)/2 / (87 AKI).

Fuel Capacity:

Approximately 2.6 gallons (9.8 liters).

Oil Type:

High-quality synthetic 4-stroke motorcycle oil, SAE 10W-40 or 10W-50 (viscosity dependent on climate, consult manual for specific recommendation).

Oil Capacity:

Approx. 1.4 - 1.7 liters (with filter change, consult manual for exact capacity).

🔧 Transmission

Transmission Type:

Constant-mesh, 5-speed

Clutch Type:

Hydraulically operated, wet multi-plate clutch.

Gear Ratios:

Specific gear ratios provided within the workshop manual for diagnostic and repair purposes.

Final Drive:

O-ring sealed chain drive

Transmission Oil Type:

Dedicated transmission oil (e.g., Motorex Gear Oil or equivalent, consult manual for specific grade and capacity).

📐 Dimensions

Length:

Approx. 1800 mm (70.9 in)

Width:

Approx. 1200 mm (47.2 in)

Height:

Approx. 1100 mm (43.3 in)

Wheelbase:

Approx. 1260 mm (49.6 in)

Dry Weight:

Approx. 170 kg (375 lbs) (manufacturer's claimed dry weight)

Ground Clearance:

Approx. 250 mm (9.8 in)

Seat Height:

Approx. 830 mm (32.7 in)

Tire Size Front:

AT20 x 7-10

Tire Size Rear:

AT19 x 10-9

Wheel Bolt Pattern:

Not applicable for ATV wheels; typically hub-mounted.

🛡️ Safety Features

Crash Test Results:

N/A (ATVs are not subject to standard automotive crash testing).

Braking System:

Dual hydraulic disc front brakes, single hydraulic disc rear brake.

Parking Brake:

Typically a caliper integrated into the rear brake system or a separate mechanism.

Frame Construction:

Chromium-Molybdenum steel trellis frame for strength and rigidity.

Handguards:

Standard on many KTM models for hand protection.

Kill Switch:

Engine kill switch readily accessible on the handlebars.

💡 Technology Features

Instrument Cluster:

Basic digital display showing speed, odometer, trip meter, and possibly engine hour meter. No complex infotainment system.

ABS:

Not equipped with ABS.

Bluetooth:

Not equipped with Bluetooth connectivity.

Ignition System:

CDI (Capacitor Discharge Ignition) unit for ignition timing.

Efi:

No Electronic Fuel Injection; utilizes a carburetor.

🔧 Maintenance

Engine Oil Change:

Typically every 15-20 hours of use or annually, depending on operating conditions (refer to manual for precise intervals).

Air Filter Cleaning:

Frequent cleaning recommended, especially in dusty conditions (e.g., every 5-10 hours).

Spark Plug Inspection:

Inspect and gap every 10-15 hours, replace as needed.

Chain Lubrication And Adjustment:

Lubricate every 5-10 hours, adjust tension as needed.

Valve Clearance Check:

Typically every 20-30 hours or annually for high-performance engines.

Engine Oil Grade:

SAE 10W-40 or 10W-50 Synthetic Motorcycle Oil.

Coolant Type:

Proprietary or high-quality motorcycle-specific coolant with anti-corrosion additives.

Brake Fluid Type:

DOT 4 or DOT 5.1 hydraulic brake fluid.

Transmission Oil Grade:

Refer to specific KTM recommendation for transmission oil (e.g., Motorex Gear Oil 75W/80 or equivalent).

Clutch Wear:

Clutch plates can wear over time, especially with aggressive riding; regular adjustment and inspection are key.

Suspension Seals:

Fork seal leaks are common with hard riding and can be mitigated with regular cleaning and proper care.

Carburetor Tuning:

Carburetor tuning can be sensitive to altitude and temperature changes; requires proper jetting.

Radiator Performance:

Ensure cooling fins are clean and coolant levels are maintained to prevent overheating.

📚 Vehicle History

Brand Focus:

KTM is renowned for its off-road racing heritage, particularly in motocross and enduro motorcycles.

Atv Division:

KTM produced ATVs for a significant period, leveraging their motorcycle expertise. The 450 SX ATV was a key model in their performance ATV lineup.

Lc4 Engine Legacy:

The LC4 engine platform has a long and storied history in KTM's product line, known for its robust construction and torque.

Manufacturing Origin:

Typically Austria (KTM headquarters), though components might be sourced globally.

Discontinuation Of Atv Line:

KTM eventually ceased ATV production to focus on its core motorcycle business, making these models historically significant.

🏆 Awards & Recognition

Model Specific Awards:

While specific awards for the 2009-2011 450 SX ATV are not readily publicized, KTM ATVs of this era were generally well-regarded in the performance off-road community for their power and handling.

Performance Ratings:

Consistently reviewed positively for its competitive engine performance and chassis dynamics in its class during its production years.