Motorcycle Segment:
Lightweight Supermoto / Motard
Target Audience:
Enthusiasts and riders seeking agile on-road performance with a dirt bike feel.
Key Competitors:
Yamaha WR125X, Aprilia SX 125, Beta RR 125 Motard, CCM R30. Competes in the popular 125cc segment for younger riders or those seeking an economical, nimble urban or track-day machine.
Performance Focus:
Designed for agility, quick handling, and spirited riding on paved surfaces.
Design Philosophy:
Combines a capable dirt bike chassis with road-biased tires and suspension for a versatile supermoto experience.
Manual Value Proposition:
Provides comprehensive, authoritative guidance for maintaining and repairing the SM 125 S, ensuring longevity and optimal performance.
Engine:
Complete engine overhaul, including disassembly, inspection, assembly, and torque specifications for all internal components.
Fuel System:
Carburetor tuning, rebuilding, fuel pump service (if applicable), fuel filter replacement, and fuel line inspection.
Ignition System:
Spark plug specifications, ignition timing, coil testing, stator and CDI unit troubleshooting.
Cooling System:
Radiator service, coolant type and capacity, water pump inspection and replacement, thermostat operation.
Exhaust System:
Exhaust pipe and silencer removal, inspection for damage, and reinstallation procedures.
Transmission:
Clutch inspection and adjustment, gearbox disassembly and reassembly, gear shift mechanism, and transmission oil specifications.
Chassis Frame:
Frame inspection for cracks or damage, steering head bearing service, and frame component torque values.
Suspension Front:
Front fork service, including oil type, level, seal replacement, spring replacement, and damping adjustment procedures.
Suspension Rear:
Rear shock absorber service, linkage inspection, bearing lubrication, and spring pre-load adjustment.
Brakes Front:
Brake caliper service, pad replacement, disc inspection, brake fluid type and bleeding procedures.
Brakes Rear:
Rear brake caliper service, pad replacement, disc inspection, brake fluid type and bleeding procedures.
Wheels And Tires:
Wheel bearing service, spoke tensioning (if applicable), tire pressure recommendations, and wheel removal/installation.
Electrical System:
Wiring diagrams, component testing (lights, horn, signals), battery maintenance, and fuse identification.
Bodywork And Plastics:
Fairing removal and installation, seat removal, and general body panel maintenance.
Maintenance:
Routine maintenance checks, lubrication points, filter replacement intervals, and seasonal storage procedures.
Troubleshooting:
Diagnostic charts for common running issues, electrical faults, and mechanical problems.
Repair:
Step-by-step instructions for component repair, rebuilding, and replacement.
Rebuilds:
Comprehensive instructions for engine and transmission rebuilds.
Refurbishment:
Guidance on restoring various components to original specifications.
Restoration:
Detailed procedures relevant to bringing the motorcycle back to its original condition.
Diagnostic Capabilities:
Advanced diagnostic procedures for identifying and rectifying complex issues across all systems.
Rebuild Instructions Detail:
Detailed, component-level rebuild instructions with critical tolerances and specifications.
Electrical Schematics:
Inclusion of comprehensive electrical wiring diagrams for accurate troubleshooting.
Torque Specifications:
Inclusion of all critical torque specifications for fasteners and internal components.
Special Tool Requirements:
Identification and description of any specialized tools required for specific procedures.
Engine Type:
Liquid-cooled, two-stroke, single-cylinder
Displacement:
124.8 cc (9.84 cu in)
Bore X Stroke:
54 mm x 54.5 mm (2.13 in x 2.15 in)
Compression Ratio:
Approx. 8.8:1 (variations may exist based on specific market tuning)
Power Output:
Approx. 15 HP (11.2 kW) at 8,000 rpm (typical for 125cc two-strokes in this era, subject to restrictions)
Torque:
Approx. 12 Nm (8.9 lb-ft) at 7,500 rpm (estimated)
Top Speed:
Subject to rider weight, conditions, and local regulations; typically around 100-110 km/h (62-68 mph).
Carburetor:
Dell'Orto PHBH 28 DD (or similar specification)
Fuel Type:
Unleaded gasoline, minimum Octane rating of 95 (RON).
Fuel Tank Capacity:
Approximately 9.5 liters (2.5 US gallons)
Oil Mixture:
Pre-mix or separate oil injection system (depending on specific market variant and build date), typically a 2-stroke synthetic oil with a 50:1 or 40:1 ratio for pre-mix.
Length:
Approximately 2050 mm (80.7 in)
Width:
Approximately 760 mm (29.9 in)
Height:
Approximately 1170 mm (46.1 in)
Wheelbase:
Approximately 1430 mm (56.3 in)
Seat Height:
Approximately 860 mm (33.9 in)
Ground Clearance:
Approximately 280 mm (11.0 in)
Cargo Capacity:
N/A (motorcycle, no dedicated cargo space)
Dry Weight:
Approximately 105-110 kg (231-243 lbs)
Wet Weight:
Approximately 118-123 kg (260-271 lbs) (with fluids)
Safety Ratings:
Motorcycle safety is assessed by regulatory bodies and rider experience, not standardized crash ratings like cars.
Braking System:
Hydraulic disc brakes front and rear for effective stopping power. Front typically a larger diameter disc (e.g., 300mm) with a dual-piston caliper.
Lighting:
Headlight, taillight, brake light, and turn signals for visibility and signaling.
Chassis Design:
Rigid frame and capable suspension contribute to stable handling and rider control.
Tire Selection:
Supermoto-style tires offer good grip on paved surfaces. Manual will specify recommended tire pressures and types.
Oil Change Interval:
Typically every 3,000 - 5,000 km (1,800 - 3,000 miles) or annually. For two-stroke, oil injection system checks are critical.
Spark Plug Replacement:
Recommended every 5,000 - 7,500 km (3,000 - 4,500 miles), depending on plug type and usage.
Air Filter Cleaning Replacement:
Frequent checks recommended, especially if ridden in dusty conditions. Clean every 1,000-2,000 km, replace as needed.
Chain Lubrication Adjustment:
Lubricate every 500 km (300 miles) and check/adjust tension every 1,000 km (600 miles).
Top End Rebuild Recommendation:
For two-strokes, piston and ring inspection/replacement typically recommended around 10,000 - 15,000 km (6,000 - 9,000 miles) depending on riding style.
Engine Oil:
For two-stroke pre-mix: High-quality synthetic 2T engine oil meeting JASO FD or ISO-L-EGD standards. For separate oil injection: Specific 2T injector oil recommended by Husqvarna.
Transmission Oil:
SAE 10W/40 or 20W/40 API GL-3 or GL-4.
Coolant:
Ethylene glycol-based coolant with corrosion inhibitors. Mixture ratio typically 50:50 with distilled water. Capacity approx. 1.5 liters.
Brake Fluid:
DOT 4 brake fluid.
Common Wear Items:
Clutch plates, piston rings, brake pads, chain and sprockets, wheel bearings, and exhaust packing (if equipped).
Carburetor Tuning Sensitivity:
Two-stroke carburetors can be sensitive to altitude, temperature, and fuel quality. The manual will provide baseline settings.
Cooling System Maintenance:
Regular flushing and coolant checks are important to prevent overheating, especially during spirited riding.
Husqvarna Motorcycles Legacy:
Husqvarna is one of the oldest motorcycle manufacturers, with a rich history in off-road and racing disciplines. Known for its Swedish engineering and robust designs.
Sm 125 Series Development:
The SM 125 S represents Husqvarna's entry into the popular 125cc supermoto segment, leveraging their experience from motocross and enduro bikes. This model aimed to provide an accessible yet performance-oriented supermoto machine.
Manufacturing Location:
Primarily produced in Italy during this period, under ownership that included Cagiva Group.
Production Era:
Early 2000s, a period where lightweight supermotos gained significant popularity in Europe.