Segment:
Off-road competition/Enduro motorcycles
Target Audience:
Owners, mechanics, and enthusiasts of 1990 Husqvarna WR series motorcycles.
Competitors 1990:
KTM (e.g., 250 EXC), Yamaha (e.g., YZ250WR), Honda (e.g., CR250R), Suzuki (e.g., RM250).
Model Focus:
Performance-oriented off-road capability for the WR (Wide Range) series.
Manual Advantage:
Most complete OEM information for accurate maintenance and repair, crucial for vintage off-road bikes.
Engine:
Complete engine disassembly, assembly, tuning, and troubleshooting for all variants.
Transmission:
Gearbox inspection, repair, and maintenance procedures.
Suspension:
Front fork (upside-down telescopic, hydraulic) and rear shock absorber service, including adjustments and rebuilds.
Brakes:
Front and rear brake system maintenance, including caliper service, hydraulic line bleeding, and pad replacement.
Electrical:
Ignition system, lighting, wiring diagrams, and component troubleshooting.
Fuel System:
Carburetor identification, tuning, and rebuilding procedures.
Cooling System:
Air-cooled engine specifications and maintenance.
Frame Chassis:
Frame inspection, component mounting, and general chassis maintenance.
Bodywork:
Plastics, seat, and fuel tank maintenance and removal.
Maintenance:
Regular service checks, lubrication points, filter replacements, and fluid changes.
Repair:
Step-by-step instructions for common and complex repairs across all systems.
Troubleshooting:
Diagnostic tables and flowcharts for identifying and resolving common issues.
Diagnostics:
Identification of potential failures and methods for checking component functionality.
Overhaul:
Detailed procedures for complete engine and gearbox rebuilds.
Level Of Detail:
Comprehensive OEM-level technical information, suitable for professional mechanics and advanced DIY enthusiasts.
Type:
Two-stroke, single-cylinder, liquid-cooled (typically, though air-cooled variants existed for some models/years - manual confirms specific cooling for 1990 WR)
Bore X Stroke 240:
66.4 mm x 72 mm (approximate, to be confirmed by manual)
Bore X Stroke 250:
67.7 mm x 72 mm (approximate, to be confirmed by manual)
Bore X Stroke 260:
68 mm x 72 mm (approximate, to be confirmed by manual)
Displacement 240:
238 cc (approximate, to be confirmed by manual)
Displacement 250:
246 cc (approximate, to be confirmed by manual)
Displacement 260:
250 cc (approximate, to be confirmed by manual)
Horsepower:
Estimated 35-45 HP (dependent on specific model and tuning, manual provides exact figures)
Torque:
Manual provides specific torque figures for each displacement variant.
Carburetor Type:
Likely Mikuni VM or equivalent, manual will specify exact model and jetting.
Fuel Type:
Premium unleaded gasoline with appropriate 2-stroke oil mixture (manual specifies ratio).
Reed Valve System:
Standard for performance two-strokes of this era; manual details inspection and replacement.
Type:
6-speed manual transmission
Optional Gearboxes:
N/A for this model year, standard 6-speed.
Clutch Type:
Wet, multi-plate, cable-actuated clutch.
Gear Ratios:
Manual provides specific gear ratios for each of the 6 speeds.
Transmission Oil Spec:
Manual specifies type and capacity (e.g., SAE 80W or 10W-40 motorcycle gear oil).
Wheelbase:
Manual will provide specific wheelbase length for accurate geometry.
Dry Weight:
Typically around 230-250 lbs (104-113 kg), manual confirms exact figure.
Fuel Capacity:
Approx. 2.5 - 3.0 gallons (9.5 - 11.4 liters), manual confirms exact capacity.
Gross Vehicle Weight Rating:
Manual will list the GVWR for safe operation.
Front Wheel Size:
21 inches
Rear Wheel Size:
18 inches
Front Tire Size:
Manual specifies recommended sizes (e.g., 80/100-21).
Rear Tire Size:
Manual specifies recommended sizes (e.g., 100/100-18).
Oil Change Interval:
Manual specifies gearbox oil change intervals based on operating hours or mileage.
Air Filter Cleaning:
Frequent cleaning recommended, manual details procedure and intervals.
Spark Plug Replacement:
Manual provides recommended spark plug types and replacement intervals.
Engine Oil Type:
Manual specifies the correct 2-stroke premix ratio and type of oil for the fuel.
Cooling System Fluid:
Manual specifies coolant type and mixture for liquid-cooled variants.
Carburetor Fouling:
Common issue in two-strokes; manual details cleaning and tuning.
Clutch Wear:
Wear on clutch plates is common with hard use; manual details inspection and replacement.
Suspension Seals:
Fork seals can degrade over time; manual provides guidance on replacement.
Piston Ring Wear:
Manual provides specifications for piston ring gap and replacement intervals.
Husqvarna Heritage:
Husqvarna is one of the oldest motorcycle manufacturers, with a strong heritage in off-road racing and innovation since its inception.
Wr Series Development:
The WR (Wide Range) series was developed for enduro and off-road competition, offering a balance of power, suspension travel, and handling.
Manufacturing Location:
Sweden (traditional Husqvarna manufacturing base).
Model Significance:
The 1990 models represent a period of refinement in Husqvarna's off-road offerings before major ownership changes.
