Segment:
Lightweight Supermoto / Motard
Target Audience:
Enthusiast owners, independent motorcycle mechanics, DIY repairers
Competitors:
Yamaha WR125, Honda CRF150 (SM variants), KTM EXC 125 (SM variants)
Diagrams:
Abundant exploded views and technical diagrams for easy part identification and assembly guidance.
Illustrations:
Detailed illustrations and photographs accompany repair procedures.
Accessibility:
Instant download in PDF format, compatible with all major operating systems (PC & Mac).
Instruction Style:
Step-by-step instructions designed to simplify complex repair tasks.
Engine:
Complete engine overhaul, top-end, bottom-end, cooling system, lubrication system
Fuel System:
Carburetor tuning and rebuilding, fuel delivery, fuel tank and lines
Ignition System:
CDI ignition, spark plug specifications, troubleshooting
Transmission:
Gearbox disassembly, assembly, lubrication, clutch operation
Chassis:
Frame inspection and repair, suspension (forks, shock absorber), steering system
Brakes:
Front and rear brake systems, caliper maintenance, fluid replacement, bleeding procedures
Electrical System:
Wiring diagrams, lighting, charging system, battery maintenance, switchgear
Exhaust System:
Exhaust pipe and silencer maintenance
Bodywork And Trim:
Fenders, seat, fuel tank, fairings (if applicable), graphics
Maintenance:
Oil changes, filter replacements, chain adjustment, lubrication points
Troubleshooting:
Diagnostic flowcharts, common problems and solutions
Repair:
Step-by-step instructions for all major component repairs and replacements
Overhaul:
Complete engine and gearbox rebuild procedures
Adjustments:
Carburetor idle, valve clearance (if applicable), clutch and brake levers
Depth:
Comprehensive: covers routine maintenance to full engine and gearbox rebuilds, including detailed diagnostics.
Engine Type:
Single-cylinder, 2-stroke, liquid-cooled
Bore X Stroke:
54 mm x 54.5 mm (typical for this era 125cc 2-stroke)
Compression Ratio:
8.2:1 (typical)
Power Output:
Approx. 15-20 HP (depending on market and tuning)
Torque:
Specific torque figures not readily available, typically around 10-12 Nm.
Carburetor:
Dell'Orto PHBH 28 (common fitment)
Fuel Type:
Unleaded gasoline with 2-stroke oil pre-mix (typically 2% or 50:1 ratio)
Coolant Type:
Ethylene Glycol based antifreeze mixture
Type:
Pre-mix or separate oil injection system (depending on specific sub-model/market)
Recommended Oil:
High-quality 2-stroke motorcycle oil meeting JASO FD or API TC specifications.
Type:
6-speed constant mesh
Gear Ratios:
Specific ratios detailed in manual; typical for off-road/motard gearing.
Transmission Oil Type:
10W-40 or 10W-50 motorcycle gear oil (API GL-4 or GL-5)
Transmission Oil Capacity:
Approx. 0.8 - 1.0 Liters (refer to manual for exact capacity)
Safety Standards:
Meets relevant European EC/EEC standards for light motorcycles (varies by market).
Braking System:
Disc brakes front and rear for effective stopping power.
Tires:
Sport-oriented tires with a focus on grip for road and light off-road use.
Lighting:
Headlight, taillight, brake lights, turn signals for visibility.
Frame Construction:
Robust steel frame designed for agility and durability.
Oil Change:
Every 10-15 operating hours or annually (for gearbox oil).
Air Filter:
Clean/replace every 5-10 operating hours or as needed based on conditions.
Spark Plug:
Inspect and clean/replace every 20-30 operating hours.
Chain Lubrication:
Lubricate every 500-700 km or after riding in wet conditions.
Top End Rebuild:
Recommended every 50-70 operating hours for optimal performance in 2-stroke engines.
Brake Fluid:
DOT 4 (refer to manual for specific front/rear system requirements if different).
Fork Oil:
SAE 5W or 10W (refer to manual for precise type and quantity)
Carburetor Tuning:
Can be sensitive to altitude and temperature changes; requires periodic tuning.
2-Stroke Engine Maintenance:
Requires diligent adherence to 2-stroke oil mixture and regular top-end inspections for longevity.
Suspension Seals:
Front fork and rear shock seals can wear over time, requiring replacement.
Manufacturer:
Husqvarna Motorcycles AB, Sweden (historically, later ownership changes).
Segment Introduction:
Husqvarna has a long history in off-road and competition motorcycles, adapting models for supermoto use.
Production Period:
The SM 125 S platform was produced throughout the early 2000s.