Market Position:
The Polaris Sport 400 was positioned as a capable sport-utility ATV, offering a balance of performance and versatility for recreational riders and utility tasks. It competed in a segment with other manufacturers' mid-size sport ATVs.
Competitive Analysis:
Competed against models from Yamaha (like the Wolverine), Honda (like the FourTrax series), Suzuki (like the QuadRunner), and Kawasaki (like the Bayou) in the 400cc class. Key differentiators often included suspension travel, engine power delivery, and specific feature sets like shaft drive vs. chain drive or independent rear suspension.
Key Features:
The 1999 Sport 400 likely featured a 2-stroke, liquid-cooled engine (though air-cooled variants existed for Polaris), a 2WD drivetrain, and a capable suspension system for its era. Its focus was on nimble handling and a sporty riding experience.
Systems Covered:
Engine (disassembly, assembly, troubleshooting, tuning), Fuel System (carburetor, fuel pump, lines), Ignition System (CDI, spark plug, coil), Cooling System (air cooling), Drivetrain (transmission, chain drive, differential), Suspension (front and rear A-arms, shocks, springs), Steering System (handlebars, tie rods, steering column), Braking System (hydraulic disc brakes, master cylinder, calipers, lines), Electrical System (wiring diagrams, lighting, starter, battery), Chassis and Frame, Bodywork and Plastics, Wheels and Tires, Specifications, Torque Values, Special Tools.
Procedures Included:
Routine maintenance (oil changes, filter replacements, spark plug checks), Engine repair (top-end, bottom-end, valve adjustment if applicable), Carburetor service and tuning, Transmission service, Suspension adjustments and component replacement, Brake system bleeding and component replacement, Electrical troubleshooting and component testing, Chassis lubrication and inspection, Tire and wheel service, Clutch inspection and adjustment.
Technical Depth:
Comprehensive. Covers from basic user maintenance and inspection to in-depth component overhaul, diagnostics, and repair. Suitable for both amateur mechanics and professional technicians.
Diagnostic Procedures:
Includes step-by-step troubleshooting guides and diagnostic charts for common mechanical and electrical issues. Aids in pinpointing the root cause of problems.
Technical Specifications:
Provides detailed specifications for all components, including dimensions, tolerances, clearances, and torque values for fasteners. Essential for accurate assembly and repair.
Diagrams Illustrations:
Contains exploded views, wiring diagrams, and service illustrations to aid in understanding component relationships and disassembly/assembly sequences.
Bodywork Repair:
Procedures for removal, installation, and repair of plastic body panels, fenders, and bumpers.
Suspension Components:
Detailed information on A-arms, ball joints, tie rods, shocks, springs, and bushings, including disassembly, inspection, and replacement.
Electrical Schematics:
Complete color-coded wiring diagrams for all electrical circuits, including lighting, ignition, starting, and accessories.
Wheel Hub Bearings:
Procedures for servicing and replacing wheel hub bearings, critical for smooth operation and preventing premature wear.
Throttle Control:
Inspection, adjustment, and repair of the throttle cable and thumb throttle assembly.
Brake Calipers Pistons:
Service and overhaul procedures for brake calipers, including piston seals and bleeding mechanisms.
File Format:
Likely PDF; supports printing of select pages or the entire manual.
Print Quality:
High quality, enabling clear reproduction of diagrams, illustrations, and text.
Binding Type:
Digital download, implying print-on-demand or digital viewing. If printed, typically spiral or comb binding for lay-flat usability.
Paper Type:
N/A (Digital Format)
Completeness:
Complete Official Full Factory Service Repair Manual.
Searchability:
If in PDF format, it is likely text-searchable, allowing for quick location of specific topics or components.
Primary Engine:
Polaris 398cc, 2-stroke, liquid-cooled, single-cylinder engine (common configuration for this model year).
Horsepower:
Estimated 30-35 HP (typical for this class and engine size in 1999).
Torque:
Estimated 25-30 lb-ft (typical for this class and engine size in 1999).
Fuel System:
Carburetor (likely a Mikuni VM series or similar, specific model would be in the manual). Fuel tank capacity typically around 3-4 gallons.
Ignition:
CDI (Capacitor Discharge Ignition) system.
Lubrication:
Premix or Oil Injection system for the 2-stroke engine. Manual will specify oil type and ratio.
Cooling System:
Liquid Cooling with radiator, fan, and coolant reservoir. Manual details coolant type, capacity, and flushing procedures.
Bore X Stroke:
Specific dimensions will be provided in the manual, crucial for engine rebuilds.
Compression Ratio:
Manual will specify factory compression ratio and acceptable ranges for testing.
Transmission:
CVT (Continuously Variable Transmission) with automatic clutch and belt drive.
Optional:
Not applicable for this model year and configuration; CVT was standard.
Features:
Forward, Neutral, Reverse gears. Belt-driven system for seamless gear changes. Manual will detail belt inspection, replacement, and maintenance.
Fluid Type:
Gearcase oil, specific type and capacity to be detailed in the manual (e.g., SAE 80W-90 gear oil).
Gear Ratios:
Manual will detail the specific ratios for the CVT's low and high range (if applicable) and reverse gear.
Service Intervals:
Manual will specify detailed intervals for: Oil change (engine oil and gear oil), spark plug inspection/replacement, air filter cleaning/replacement, chain adjustment and lubrication, brake fluid flush, coolant flush (if applicable), general inspection of suspension, steering, and electrical components. Typically, engine oil changes every 100 hours or annually, chain maintenance more frequently.
Engine Oil Type:
2-stroke oil injection/premix. Manual will specify API-TC or JASO FD certified oil. Specific viscosity grade for oil injection systems.
Gear Oil Type:
Likely SAE 80W-90 gear oil for the transmission/gearcase.
Brake Fluid Type:
DOT 3 or DOT 4 hydraulic brake fluid (manual will specify).
Known Issues:
Common issues for 2-stroke ATVs of this era can include carburetor gumming/fouling, exhaust port blockage (carbon buildup), clutch wear, CVT belt slippage/wear, suspension component wear (bushings, ball joints), and electrical connections corrosion. The manual will provide diagnostic procedures for these and other potential problems.
Part Numbers:
Manual will contain extensive OEM part numbers for all replaceable components, essential for sourcing correct parts.
Tire Pressure Front:
Manual will specify recommended pressure (e.g., 5-7 PSI).
Tire Pressure Rear:
Manual will specify recommended pressure (e.g., 5-7 PSI).
Brand Heritage:
Polaris has a long history in powersports, originating in the snowmobile industry before expanding into ATVs. They became known for innovation and performance in the ATV market during the late 20th century.
Model Evolution:
The Sport 400 was part of Polaris's aggressive push into the sport ATV segment in the 1990s. It followed earlier models and paved the way for more advanced sport ATVs from the brand. The Sport 400 represented a significant step in performance and features for Polaris in its class.
Production Years:
The Sport 400 model line was produced through the late 1990s and early 2000s, with the 1999 model representing a specific iteration.
Manufacturing Location:
Typically manufactured in the United States by Polaris Industries.
