Segment:
Sportbike / Naked Bike
Target Audience:
DIY enthusiasts, mechanics, owners of the Suzuki GSX400 (1981-1983 models)
Competitors:
Similar displacement motorcycles from Yamaha (Seca), Kawasaki (GPz/Z series), Honda (CB series) of the era.
Manual Advantage:
Comprehensive, detailed, step-by-step procedures with illustrations, instant digital access.
Vehicle Character:
Known for its inline-four engine performance and sporty styling for its time.
Engine:
Complete disassembly, assembly, inspection, adjustment, troubleshooting
Fuel System:
Carburetor service, fuel pump, fuel lines
Ignition System:
Ignition timing, spark plugs, CDI unit, coils
Transmission:
Clutch operation, gearbox disassembly, assembly, inspection
Drivetrain:
Final drive, chain maintenance, sprockets
Suspension:
Front forks (telescopic), rear shock absorber, linkages
Brakes:
Front disc brakes, rear drum/disc brake (model dependent), brake fluid, caliper service
Electrical System:
Wiring diagrams, charging system (alternator/stator, regulator/rectifier), lighting, battery, starter
Cooling System:
Air-cooled (typically) - emphasis on airflow and fin cleaning
Frame And Bodywork:
Frame inspection, body panel removal/installation, seat, fuel tank
Wheels And Tires:
Wheel bearing service, tire replacement, wheel balancing
Exhaust System:
Muffler and pipe inspection, gasket replacement
Maintenance:
Routine checks, lubrication, filter replacement, fluid changes
Troubleshooting:
Diagnostic charts, common problems and solutions
Repair:
Step-by-step instructions for all major component repairs
Disassembly Assembly:
Detailed procedures for removing and refitting components
Adjustments:
Carburetor synchronization, valve clearance, brake adjustments, chain tension
Installation Removal:
Component-specific removal and installation guides
Depth:
Comprehensive (from basic maintenance to complete engine rebuilds)
Diagrams Illustrations:
Detailed pictorial diagrams, exploded views, drawings, and photos
Special Tools:
Identification and usage of specific service tools
Specifications:
Factory specifications, allowable limits, torque values
Engine Displacement:
398 cc (approximate, can vary slightly by specific market variant)
Bore X Stroke:
53.4 mm x 44.2 mm (typical)
Compression Ratio:
9.7:1 (typical)
Valve Train:
DOHC, 16 valves (4 valves per cylinder)
Horsepower:
Approx. 40-45 HP (at crank, specific figures vary by model year and market tuning)
Torque:
Approx. 30-33 Nm (at crank, specific figures vary by model year and market tuning)
Carburetion:
Mikuni VM series (likely VM22SS or similar twin-carburetor setup for twin-cylinder models, or four Mikuni carburetors for inline-four models like the GSX400)
Fuel Type:
Unleaded gasoline (min. 87 octane recommended)
Oil Change Interval:
Every 3,000-5,000 km or annually. Refer to manual for precise intervals.
Valve Clearance Check:
Every 6,000-10,000 km. Refer to manual for precise intervals.
Chain Lubrication Adjustment:
Every 500-1,000 km. Refer to manual for precise intervals.
Engine Oil Type:
API SE/SF classification, SAE 10W-40 or 20W-50 (refer to manual for precise recommendation based on ambient temperature).
Brake Fluid Type:
DOT 3 or DOT 4 hydraulic brake fluid.
Coolant Type:
N/A (Air-cooled)
Common Problems:
Carburetor synchronization drift, stator/rectifier failure, aging electrical connectors, wear on suspension bushings.
Preventative Measures:
Regular maintenance as per manual, use of quality parts, proper storage.
