Model:
GS250, GS450, GSX250, GSX400
Model Codes:
GS250E, GS250T, GS450E, GS450L, GS450ST, GSX250E, GSX250ET, GSX400E, GSX400ET, GSX400F, GSX400FS, GSX400T, GSX400TX
Production Years Covered:
1979-1985
Target Audience:
Suzuki motorcycle owners, independent repair shops, motorcycle enthusiasts undertaking their own maintenance and repairs.
Value Proposition:
A comprehensive, factory-authorized resource for maintaining and repairing a range of popular Suzuki motorcycles from the late 1970s and early 1980s.
Manual Superiority:
Provides factory-level detail often missing in aftermarket manuals; lifelong access and multi-device compatibility offer superior value over subscription or limited-use manuals.
Comprehensiveness:
Covers all aspects of repair, servicing, and troubleshooting, ensuring no task is beyond the scope of the owner or technician.
Durability And Access:
Lifetime access and multi-device usability make it a perpetually valuable resource without recurring costs.
Manual Type:
Full Factory Service & Repair Workshop Manual
Format:
Digital Download (PDF)
Digital Features:
Printable, Usable on multiple devices and computers, Lifetime access, No expiry
Estimated Page Count:
Hundreds of pages (specific count not provided, but described as 'very detailed')
Engine Overhaul:
Complete engine disassembly, inspection, repair, and reassembly procedures for all covered models and variants.
Fuel System:
Carburetor tuning, cleaning, and rebuilding; fuel pump operation; fuel tank and line maintenance.
Ignition System:
Ignition timing adjustment, spark plug specifications, coil testing, CDI unit diagnosis.
Transmission And Drivetrain:
Clutch operation, gearbox disassembly and assembly, final drive maintenance, chain and sprocket care.
Suspension And Steering:
Front fork servicing (oil changes, seal replacement), rear shock absorber maintenance, steering head bearing adjustment, swingarm lubrication.
Braking System:
Front and rear brake caliper maintenance, master cylinder servicing, brake pad replacement, brake fluid bleeding procedures.
Electrical System:
Wiring diagrams, lighting system diagnosis, battery testing, charging system (stator, regulator/rectifier) troubleshooting, starter motor operation.
Chassis And Bodywork:
Frame inspection, fairing removal and installation, seat maintenance, fuel tank removal and installation, exhaust system care.
Routine Maintenance:
Oil and filter changes, spark plug replacement, air filter cleaning/replacement, chain adjustment, brake checks, tire pressure checks.
Troubleshooting:
Diagnostic procedures for common problems, symptom-based troubleshooting guides, electrical fault finding.
Major Repairs:
Engine rebuilds, transmission overhauls, suspension upgrades, electrical system repairs.
Component Replacement:
Step-by-step guides for replacing all major and minor components.
Depth Of Information:
Comprehensive, covering everything from basic servicing to full engine and transmission rebuilds, including detailed torque specifications and clearances.
Diagrams And Illustrations:
Hundreds of detailed photos and exploded diagrams to guide repair processes.
Compatibility:
Windows and MAC OS
Searchability:
Likely text-searchable PDF (implied by 'professional manual' and digital format, though not explicitly stated)
Print Capability:
Single pages or entire manual printable
Binding Format:
Not Applicable (Digital Download)
Paper Quality:
Not Applicable (Digital Download)
Engine Configurations:
Air-cooled, 4-stroke, DOHC (Double Overhead Camshaft), inline twins.
Engine Configurations Detail
Gs250 / Gsx250:
Typically 247cc displacement, 2 valves per cylinder.
Gs450 / Gsx400:
Typically 448cc (GS450) or 398cc (GSX400) displacement, 2 valves per cylinder.
Gs250 Power Output:
Approx. 26-30 hp (specific figures vary by model variant and year).
Gs450 Power Output:
Approx. 40-45 hp (specific figures vary by model variant and year).
Gsx250 Power Output:
Approx. 30-35 hp (specific figures vary by model variant and year).
Gsx400 Power Output:
Approx. 45-50 hp (specific figures vary by model variant and year).
Carburetor Type:
Twin Mikuni VM or similar side-draft carburetors (specific model dependent).
Fuel Delivery:
Gravity feed from fuel tank to carburetors.
Transmission Type:
5-speed constant mesh manual transmission.
Shaft Drive Availability:
Some GS450 models (e.g., GS450L) featured shaft drive as an alternative to chain drive.
Clutch Type:
Wet, multi-plate, cable-actuated clutch.
Safety Standards:
Designed to meet safety regulations of their respective production years.
Braking System Type:
Front: Disc brake; Rear: Disc or Drum brake (model dependent).
Lighting:
Headlight, taillight, brake light, turn signals.
Oil Change Interval:
Typically every 3,000-5,000 km (approx. 1,800-3,000 miles) or 6-12 months, whichever comes first (refer to manual for exact specification).
Valve Adjustment Interval:
Typically every 6,000-10,000 km (approx. 3,700-6,200 miles) (refer to manual for exact specification).
Engine Oil Type:
API SE or SF classification, SAE 10W-40 or 20W-50 viscosity recommended (refer to manual for precise specification).
Engine Oil Capacity:
Approx. 2.0 - 2.5 liters (depending on model and filter change) (refer to manual for exact specification).
Brake Fluid Type:
DOT 3 or DOT 4 brake fluid (refer to manual for exact specification).
Fork Oil Type:
Typically SAE 10W fork oil (refer to manual for exact specification).
Common Wear Items:
Cam chain tensioner, clutch plates, fork seals, wheel bearings, and rectifier/regulator units are common wear items.
Electrical Reliability:
Older electrical components, particularly the regulator/rectifier and stator, can be prone to failure over time.
Carburetor Issues:
Gumming and blockage of carburetors due to old fuel or infrequent use is a common issue requiring cleaning and rebuilding.
Comprehensive Schedule:
The manual provides detailed, mileage-based (or time-based) maintenance schedules for all major systems.
Suzuki Motorcycle Legacy:
Suzuki has a long-standing reputation for producing reliable, performance-oriented motorcycles across various classes.
Gs Series Development:
The GS series represented Suzuki's expansion into the popular mid-size and performance motorcycle market in the late 1970s and early 1980s, offering a blend of performance and affordability.
Gsx Series Development:
The GSX designation often indicated a more performance-oriented variant, sometimes with DOHC engines and sportier styling.
Manufacturing Location:
Primarily Japan.
