Atv Segment:
Sport ATV, aimed at recreational riding and light trail use.
Competitors Era:
Competed with models from Yamaha (Warrior, Banshee), Suzuki (QuadSport), and Kawasaki (Bayou, Lakota) during its production run.
Sport Focus:
Designed for agile handling and sporty performance, distinguishing it from utility-focused ATVs.
Engine Type:
2-stroke engine for a power-to-weight advantage characteristic of sport ATVs.
Engine:
Detailed breakdown of the 398cc liquid-cooled 2-stroke engine, including disassembly, assembly, timing, and adjustments.
Fuel System:
Carburetor (Mikuni VM34-3) inspection, cleaning, adjustment, jetting, and fuel pump operation.
Ignition System:
CDI ignition system, stator, coil, spark plug specifications, and troubleshooting.
Cooling System:
Radiator, fan, thermostat, water pump, hoses, and coolant specifications and maintenance.
Transmission Drivetrain:
CVT (Continuously Variable Transmission) system, drive belt inspection and replacement, clutch operation, and final drive components (chain/sprockets).
Suspension:
Front and rear suspension systems, shock absorber adjustments, bushings, and ball joint service.
Brakes:
Hydraulic disc brake system, caliper maintenance, pad replacement, fluid bleeding, master cylinder service, and brake line inspection.
Electrical System:
Wiring diagrams, lighting system, battery maintenance, starter motor, and charging system troubleshooting.
Chassis Frame:
Frame inspection, steering system service, and handlebar components.
Bodywork Trim:
Fender, seat, and panel removal and installation procedures.
Routine Maintenance:
Oil changes, filter replacements, chain lubrication, spark plug checks, and general inspection procedures.
Troubleshooting Diagnostics:
Step-by-step diagnostic flowcharts for common starting, running, and electrical issues.
Engine Repair:
Top-end rebuilds (piston, rings, cylinder), crankshaft seal replacement, and valve adjustments (if applicable, though likely none on this 2-stroke).
Transmission Service:
CVT clutch inspection, adjustment, and replacement procedures; drive clutch sheave service.
Brake System Repair:
Brake caliper overhaul, piston seal replacement, and hydraulic system bleeding.
Electrical Diagnostics:
Using a multimeter for testing ignition components, charging system, and lighting circuits.
Suspension Component Replacement:
Shock absorber and spring replacement procedures.
Steering Component Service:
Tie rod end replacement and steering stem bearing service.
Depth Of Information:
Detailed technical specifications, torque values, clearances, and diagnostic procedures for professional-level repairs and maintenance.
Diagnostic Tools:
Implied use of basic hand tools, torque wrenches, and a multimeter for troubleshooting.
Component Rebuilds:
Covers complete rebuilds of major components like the engine and carburetor.
Engine Type:
2-stroke, 1-cylinder, liquid-cooled
Displacement:
398cc (24.3 cubic inches)
Bore X Stroke:
80.0 mm x 79.0 mm
Carburetor:
Mikuni VM34-3
Horsepower:
Approx. 30-35 HP (estimated for this class and era)
Torque:
Not explicitly stated in product info, but expected to be robust for its displacement.
Fuel Type:
Unleaded gasoline (typically 87-91 octane recommended)
Fuel Mixture:
Automatic oil injection (pre-mix not required)
Oil Type:
Polaris 2-stroke synthetic oil injection lubricant (refer to manual for specific part numbers/types)
Cooling Medium:
Liquid Cooling
Coolant Type:
Ethylene Glycol based antifreeze with rust inhibitors (refer to manual for specific mix ratio)
Engine Oil Change:
Every 20-40 operating hours or annually. Specific interval in manual.
Air Filter Cleaning:
Clean every 10-20 operating hours, replace as needed. Refer to manual for specific cleaning instructions (e.g., washing and oiling).
Spark Plug Check:
Inspect at every 20 operating hours. Replace as needed.
Cvtvbelt Inspection:
Inspect belt for wear and damage at every 40 operating hours. Replace based on wear.
Brake Fluid Flush:
Every 1-2 years or as recommended by manual.
Engine Oil Type:
Polaris 2-stroke synthetic oil injection lubricant. Manual specifies exact type and part number.
Transmission Fluid:
Refer to manual for specific CVT fluid (e.g., Polaris synthetic CVT fluid or compatible ATF). Capacity: Approx. 2.5-3.0 liters.
Brake Fluid Type:
DOT 3 or DOT 4 hydraulic brake fluid (refer to manual for precise specification).
Coolant Type:
Ethylene Glycol based antifreeze, 50/50 mix with distilled water.
Common Wear Item Cvts:
CVT drive belt wear is common; regular inspection and replacement are crucial for performance.
2 Stroke Carb Cleaning:
Carburetor can be prone to clogging if fuel is stale or dirty; regular cleaning is advisable.
Cooling System Maintenance:
Ensure radiator fins are clean and coolant is fresh to prevent overheating, especially on the liquid-cooled 2-stroke.
Ignition Coil Failure:
Ignition coils can fail over time; troubleshooting steps in the manual are vital.
Polaristech Advancement:
Polaris has a long history in powersports, evolving from snowmobiles to ATVs and UTVs, known for innovation.
Sport Lineup:
The Sport 400 was part of Polaris's growing sport ATV lineup, competing in a burgeoning market segment.
Engine Development:
The 398cc 2-stroke engine was a common displacement for powerful recreational ATVs of this period.
Manufacturing Location:
Manufactured by Polaris Industries, typically in Minnesota, USA.
Production Period:
Produced as new models from 1996 to 1998, with potential carryover in subsequent years for existing stock.
