Target User:
Enthusiast riders and professional mechanics seeking to maintain, repair, or restore their KTM 125/200 SX, MXC, or EXC models from 1999.
Value Proposition:
Provides essential factory-level information, enabling owners to perform complex tasks often reserved for dealerships, saving time and money while ensuring proper maintenance and repair.
Content Focus:
Detailed diagrams, step-by-step procedures, torque specifications, electrical schematics, and troubleshooting guides specific to the 1999 model year and its variants.
Engine Systems:
Top-end (cylinder, piston, ring, cylinder head), bottom-end (crankshaft, connecting rod, bearings), lubrication system, cooling system (if applicable to specific models), fuel system (carburetor, fuel delivery), ignition system, exhaust system.
Transmission Systems:
Clutch operation and adjustment, gearbox disassembly and reassembly, gear selection mechanism, shift drum and forks, lubrication.
Chassis Systems:
Frame inspection and repair, suspension (forks, rear shock absorber, linkages), steering system (headset bearings, steering stem), wheel bearings, brake systems (hydraulic front and rear, caliper, master cylinder, brake lines, pads, rotors), clutch actuation mechanism, throttle control, cable routing.
Electrical Systems:
Wiring diagrams, lighting system (headlight, taillight, brake light, turn signals if equipped), ignition coil, stator, CDI unit, battery charging system, starter motor (if electric start equipped), fuse box, switches, relays.
Bodywork And Plastics:
Fairing removal and installation, seat, fuel tank mounting, fender replacement, graphics application.
Preventive Maintenance:
Oil change intervals and specifications, air filter cleaning and replacement, spark plug inspection and replacement, chain adjustment and lubrication, brake pad wear inspection, suspension service intervals, bolt torque checks.
Diagnostic Procedures:
Troubleshooting common issues (e.g., starting problems, poor performance, clutch slippage, brake fade), electrical fault finding using wiring diagrams, carburetor tuning and troubleshooting.
Repair And Rebuilding:
Complete engine teardown and rebuild, transmission overhaul, suspension fork seal replacement, brake caliper rebuilding, carburetor cleaning and rebuilding, clutch plate replacement.
Assembly And Disassembly:
Step-by-step instructions for removing and installing major components and sub-assemblies with detailed diagrams.
Depth Of Coverage:
In-depth, from basic routine maintenance to complete engine and transmission overhauls, including detailed specifications and tolerances.
Engine Type 125:
124.1 cc, 2-stroke, single-cylinder, water-cooled (liquid-cooled)
Engine Type 200:
193.2 cc, 2-stroke, single-cylinder, water-cooled (liquid-cooled)
Bore Stroke 125:
54.0 mm x 54.5 mm
Bore Stroke 200:
62.5 mm x 64.0 mm
Compression Ratio 125:
Approx. 8.8:1 (varies with exhaust/reed valve setup)
Compression Ratio 200:
Approx. 7.8:1 (varies with exhaust/reed valve setup)
Horsepower 125:
Approx. 30-35 hp (at crank, depending on variant)
Horsepower 200:
Approx. 35-40 hp (at crank, depending on variant)
Torque 125:
Approx. 20-22 Nm (at crank, depending on variant)
Torque 200:
Approx. 25-28 Nm (at crank, depending on variant)
Carburetor Type:
Keihin PWK 36 (typical for 1999 SX/MXC/EXC models, may vary slightly)
Fuel Type:
Unleaded gasoline, minimum 95 octane (RON) recommended. Pre-mix with 2-stroke oil.
Premix Ratio:
1:40 or 1:50 (2-stroke oil to gasoline), refer to manual for specific recommendation.
Reed Valve System:
V-Force or similar high-performance reed block is common and often upgrades from stock.
Transmission Type:
6-speed constant mesh gearbox
Clutch Type:
Wet multi-plate clutch, hydraulically operated
Gear Ratios:
Specific gear ratios will be detailed in the manual for each model variant.
Transmission Oil Type:
SAE 10W/40 motorcycle transmission oil, API SG or higher (refer to manual for specific brand/viscosity).
Transmission Oil Capacity:
Approx. 750-850 ml (refer to manual for precise capacity)
Frame Type:
Chromium-molybdenum steel, perimeter frame
Suspension Front Travel:
Typically 270-300 mm (WP USD forks, model dependent)
Suspension Rear Travel:
Typically 290-330 mm (WP PDS or linkage system, model dependent)
Dry Weight 125:
Approx. 95-100 kg (model dependent)
Dry Weight 200:
Approx. 100-105 kg (model dependent)
Safety Standards:
Designed to meet off-road and competition regulations of the era. No formal road safety ratings (e.g., NHTSA, Euro NCAP) apply to these competition-oriented models.
Braking System Front:
Hydraulic disc brake, Brembo caliper (typically 2-piston) with 260mm rotor
Braking System Rear:
Hydraulic disc brake, Brembo caliper (typically 1-piston) with 220mm rotor
Engine Kill Switch:
Standard handlebar-mounted kill switch for immediate engine shutdown.
Handguards:
Often fitted as standard or easily added for rider protection.
Engine Oil Change:
Every 10-15 hours of riding, or annually. Refer to manual for specific conditions.
Air Filter Cleaning:
After every few rides, or more frequently in dusty conditions.
Spark Plug Inspection:
Every 20-30 hours of riding.
Piston Ring Replacement:
Every 40-60 hours of riding (depending on usage).
Top End Rebuild:
Every 80-120 hours of riding (piston, rings, potentially cylinder honing).
Coolant Type:
Ethylene glycol based coolant, 50% mixture with distilled water. (Refer to manual for specific type and additive requirements).
Brake Fluid Type:
DOT 4 hydraulic brake fluid.
Fork Oil Type:
Specific WP fork oil, viscosity typically around SAE 5W or 7.5W (refer to manual for exact specification and oil level).
Common Wear Items:
Piston rings, clutch plates, wheel bearings, steering head bearings, pivot bearings (swingarm, linkage), spark plug, air filter, chain and sprockets.
Potential Problems:
Carburetor jetting sensitivity to altitude/temperature, reed valve wear, premature piston wear if proper premix is not used, clutch wear from aggressive riding.
Brand Focus:
KTM has a long-standing heritage in off-road racing and performance motorcycles, known for its 'Ready to Race' philosophy.
Model Lineage 125/200:
The 125 and 200 EXC/MXC/SX models represent KTM's commitment to the motocross and enduro racing scene, offering competitive performance in their respective engine classes.
Production Era:
These specific models (1999) are part of the late 1990s generation of KTM off-road bikes, characterized by significant chassis and engine development from previous years.
