Target Audience:
Suzuki GN250 owners, independent repair shops, motorcycle technicians, DIY enthusiasts
Value Proposition:
Provides essential technical data and repair procedures to maintain, diagnose, and repair the Suzuki GN250, reducing reliance on expensive dealership services.
Alternatives:
Original Suzuki factory service manuals (often scarce and expensive), generic motorcycle repair guides (less specific detail).
Detail Level:
Detailed enough for complete engine overhauls and complex electrical diagnostics.
Usability:
Well-organized sections, clear language, and helpful diagrams enhance ease of use.
Engine:
Complete disassembly, inspection, assembly, timing, valve clearance, compression testing, carburetor tuning, lubrication system, cooling system (air-cooled)
Fuel System:
Carburetor service, fuel pump, fuel lines, fuel tank maintenance
Transmission:
Clutch operation and adjustment, gear shifting mechanism, internal transmission components, lubrication
Drivetrain:
Final drive (chain and sprockets), lubrication and maintenance
Chassis:
Frame inspection and repair, suspension (front fork, rear shock absorbers), steering system, wheel bearings
Brakes:
Front and rear brake system service, hydraulic fluid replacement, pad and shoe inspection/replacement, caliper and master cylinder overhaul
Electrical System:
Ignition system (spark plug, ignition coil, CDI unit), charging system (alternator, regulator/rectifier), starting system (starter motor, battery), lighting system, wiring diagrams, fuse replacement, switch troubleshooting
Bodywork And Trim:
Panel removal and installation, seat, handlebars, fenders, fuel tank, minor body repair considerations
Routine Maintenance:
Oil changes, filter replacement, spark plug checks, chain lubrication and adjustment, brake adjustments, tire pressure checks
Troubleshooting:
Diagnostic charts for common engine performance, electrical, and mechanical issues
Disassembly And Assembly:
Step-by-step instructions for major component removal and reinstallation
Rebuilds:
Detailed procedures for engine overhaul, carburetor rebuild, brake caliper overhaul
Adjustments:
Carburetor idle speed and mixture, clutch cable, throttle cable, brake levers, chain slack
Depth Level:
Comprehensive (covers everything from basic maintenance to full engine rebuilds and electrical diagnostics)
Searchability:
Searchable text for quick information retrieval
Printability:
Printable pages for convenient workshop use
Resolution:
High-resolution scans for clear text and diagrams
Image Quality:
Clear, legible diagrams, illustrations, and photographs
Binding Type:
N/A (Digital Product)
Paper Type:
N/A (Digital Product)
Engine Type:
Air-cooled, 4-stroke, SOHC
Displacement:
249 cc (Cubic Centimeters)
Bore X Stroke:
66.0 mm x 72.0 mm (typical for this engine)
Compression Ratio:
9.2:1 (typical for this engine)
Valve Configuration:
SOHC (Single Overhead Camshaft) with 2 valves per cylinder
Horsepower:
Approximately 20-23 HP @ 7,500 RPM (estimated, varies slightly by year/market)
Torque:
Approximately 19-21 Nm @ 6,000 RPM (estimated, varies slightly by year/market)
Top Speed:
Approximately 120-130 km/h (estimated)
Fuel Economy:
Highly variable based on riding conditions, typically 50-65 MPG (estimated)
Carburetor Model:
Mikuni VM series (e.g., VM30SS or similar single carburetor, specific model may vary)
Fuel Tank Capacity:
Approximately 11 liters (2.9 US gallons, including reserve)
Fuel Type:
Unleaded gasoline, minimum 87 octane (RON+MON)/2
Transmission Type:
5-speed constant mesh manual
Clutch Type:
Wet multi-plate
Gear Ratios:
Specific ratios detailed in manual (e.g., 1st: 2.538, 2nd: 1.750, 3rd: 1.333, 4th: 1.071, 5th: 0.913)
Final Drive Type:
Chain drive
Final Drive Ratio:
Typically 2.750 (e.g., 44/16 tooth sprockets, specific details in manual)
Transmission Fluid Type:
API GL-4, SAE 80W-90 gear oil (specific recommendations in manual)
Length:
Approx. 2055 mm (80.9 inches)
Width:
Approx. 750 mm (29.5 inches)
Height:
Approx. 1100 mm (43.3 inches)
Wheelbase:
Approx. 1370 mm (53.9 inches)
Dry Weight:
Approx. 143 kg (315 lbs)
Wet Weight:
Approx. 155 kg (342 lbs) (with all fluids)
Gross Vehicle Weight Rating:
Not typically specified for motorcycles in this class, but refers to maximum load capacity.
Crash Test Ratings:
N/A (Motorcycles are not subject to the same crash testing standards as automobiles)
Braking System:
Front disc brake, Rear drum brake (standard configuration)
Lighting:
Halogen headlight, taillight, brake light, turn signals
Frame Construction:
Steel cradle frame for stability
Suspension Design:
Telescopic front forks and swingarm rear suspension with adjustable pre-load
Engine Oil Change:
Every 3,000-5,000 km (1,800-3,000 miles) or 6 months, whichever comes first (refer to manual for exact interval).
Oil Filter Replacement:
Recommended with every oil change or as specified in the manual.
Spark Plug Check And Replacement:
Check at 1,000 km (600 miles), replace as needed or at recommended intervals (e.g., 6,000-10,000 km).
Chain Lubrication And Adjustment:
Lubricate every 500 km (300 miles), adjust slack as needed or every 1,000 km (600 miles).
Valve Clearance Adjustment:
Typically every 6,000-12,000 km (3,700-7,500 miles) or as per manual, often at major service intervals.
Engine Oil Grade:
SAE 10W-40 or 10W-30, API SE, SF, or SG classification (refer to manual for precise recommendation).
Engine Oil Capacity:
Approximately 1.6 - 1.8 liters (1.7 - 1.9 US quarts) with filter change (check dipstick).
Brake Fluid Type:
DOT 3 or DOT 4 hydraulic brake fluid (ensure cleanliness and correct type).
Fork Oil Type:
SAE 10W fork oil (specific quantity and type in manual).
Common Wear Items:
Clutch plates, brake pads/shoes, chain and sprockets, fork seals, carburetor jets/needles (due to age/mileage).
Potential Problems:
Carburetor gumming if fuel sits too long, electrical connections can corrode with age, kickstart mechanism wear, exhaust system corrosion.
Diagnostic Focus Areas:
Carburetor tuning for smooth idle and acceleration, ignition system health, and general mechanical wear.
Manufacturer Origin:
Japan
Suzuki Motorcycle History:
Suzuki Motor Corporation has a long history of producing reliable and innovative motorcycles across various categories, from small commuter bikes to high-performance sportbikes and off-road machines.
Gn Series Purpose:
The GN series was designed as a versatile, user-friendly, and stylish motorcycle, often targeting the commuter and light touring segments. The GN250 represented a popular displacement for this market.
Gn250 Positioning:
Positioned as a reliable and economical all-rounder, suitable for daily commuting and recreational riding.
Production Period:
The Suzuki GN250 was produced from the early 1980s through the early 2000s in various forms and markets.
Manufacturing Locations:
Primarily manufactured in Japan, with potential assembly in other international locations.